British Army during the First World War: Difference between revisions

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The British Army during World War I fought the largest and most costly war in its long history.^[1] Unlike the French and German Armies at the beginning of the conflict its units were all volunteers not conscripts.^[2] It was also considerably smaller than its French and German counterparts.^[3]

The outbreak of World War I in August 1914 saw the bulk of the changes in the Haldane reforms put to the test. The British Expeditionary Force (BEF) of six divisions was quickly sent to the Continent, while the Territorial Forces fourteen divisions and Reserves were mobilised as planned to provide a second line.^[4]

During the war there were three distinct British Armies. The 'first' army was the small volunteer force of 400,000 soldiers, over half of which were posted overseas to garrison the British Empire. This total included the Regular Army and reservists in the Territorial Force. Together they formed the BEF, for service in France and became known as the Old Contemptibles. The 'second' army was Kitchener's Army, formed from the volunteers in 1914–1915 destined to go into action at the Battle of the Somme. The 'third' was formed after the introduction of conscription in January 1916 and by the end of 1918 the army had reached its peak of strength of four million men and could field over seventy divisions.

The war also saw the introduction of new weapons and equipment. The Maxim machine gun had been replaced by the improved Vickers and the Lewis machine gun was introduced, the Brodie helmet was supplied for better personnel protection against shrapnel and the Mark I tank was invented to try and end the stalemate of trench warfare.

The vast majority of the army fought in France and Belgium on the Western Front but some units were engaged in the Mediterranean, the Middle East, Africa and Mesopotamia, mainly against the Ottoman Empire. One battalion also fought in China during the Siege of Tsingtao.

The British Army during World War I could trace its origins to the increasing demands of imperial expansion together with inefficiencies highlighted during the Crimean War, which led to the Cardwell and Childers Reforms of the late 19th century. These gave the British Army its modern shape, and defined its regimental system. The Esher Report in 1904, recommended radical reform of the British Army, such as the creation of an Army Council, a General Staff and the abolition of the office of Commander in Chief of the Forces and the creation of a Chief of the General Staff.^[5] The Haldane Reforms in 1907, created an expeditionary force of seven divisions, it also reorganized the volunteers into a new Territorial Force of fourteen cavalry brigades and fourteen infantry divisions, and changed the old militia into the special reserve to reinforce the expeditionary force.^[6]

The last conflict the British army had been in before World War I, was the Second Boer War (1899–1902). In the interim years the army had been prepared and primarily called upon for Empire matters and the ensuing colonial wars. ^[7]

At the outbreak of the war in August 1914, the British Army was a small professional force, almost half of which were posted overseas in garrisons throughout the British Empire. In August 1914, 74 of the 157 infantry battalions and 12 of the 31 cavalry regiments were posted overseas.^[8] The regular army was supported by reservists and soldiers of the Territorial Force.^[8] The Army consisted of 247,432 regular troops organized in four Guards regiments, 68 infantry regiments, 31 cavalry regiments, artillery and other support arms, serving at home and overseas around the British Empire.^[8] The majority of the line infantry regiments had two battalions in the Regular Army, one of which was usually overseas, while the other trained recruits in the United Kingdom.^[8] In August 1914, in addition to the Regular Army, there were three forms of reserves. The Army Reserve of retired soldiers was 145,350 strong. They were paid 3 Shillings and 6 pence a week (17.5 pence today) and had to attend twelve training days per year.^[9] The Special Reserve had another 64,000 men and was a form of part time soldiering, similar to the Territorial Force. A Special Reservist had an initial six months full time training and was paid the same as a regular soldier during this time, they then had three or four weeks training per year thereafter.^[9] The National Reserve had some 215,000 men, and was a register maintained by Territorial Force County Associations of all those who had military experience, but who had no other reserve obligation.^[8][9] This totalled, on paper, a mobilized force of almost 700,000 men, however, only 150,000 men were able to be formed into the British Expeditionary Force (BEF) that was sent to the continent. This consisted of six infantry divisions and one of cavalry.^[8] The Royal Flying Corps was included with the army until 1918 and at the outbreak of the war consisted of eighty four aircraft.^[8]

Britain began the war with six regular and fourteen reserve divisions. During the war a further six regular, fourteen Territorial, thirty six Kitchener's Army and six other divisions including the Naval Division from the Royal Navy were formed.^[10]

The 1914 divisions had three infantry brigades each of four battalions with two machine guns per battalion, (twenty four in the division). They also had three field artillery brigades with fifty four 18 pounder guns, one field Howitzer brigade with eighteen 4.5 inch howitzers, one heavy artillery battery with four 60 pounder guns, two engineer companies, one signals company, one cavalry squadron, one cyclist company and divisional headquarters support detachments.^[11][12]

Over the course of the war the composition of the division changed and gradually there was an increased emphasis upon providing the infantry divisions with organic fire support. By 1918, a British division consisted of three infantry brigades, each of three battalions. Each of these battalions had thirty six Lewis machine guns (making a total of 324 Lewis guns in the division as opposed to twenty four Vickers guns in 1914). Additionally there was a divisional machine gun battalion, equipped with sixty four Vickers machine guns in four companies of sixteen guns each and each brigade in the division had a mortar battery with eight Stokes Mortars.^[8] The artillery also changed the composition of its batteries at the start of the war there were three batteries with six guns per brigade, they then moved to four batteries with four guns per brigade and finally in 1917, to four batteries with six guns per brigade to economise on battery commanders.^[12] In this way, the army would change drastically over the course of the war, reacting to the various developments, from the mobile war fought in the opening weeks of the war to the static trench warfare of 1916 and 1917. The cavalry of the expeditionary force represented 9.28 percent of the army, but by July 1918 would only represent 1.65 percent. Infantry would decrease from 64.64 percent in 1914 to 51.25 percent in 1918, while the Royal Engineers would increase from 5.91 percent to 11.24 percent in 1918. ^[7]

Under the terms of the Entente Cordiale, the British Army's role in a European war was to embark soldiers of the British Expeditionary Force (BEF), consisting of six infantry divisions and five cavalry brigades, arranged into two Army corps, the I Corps under the command of Haig and the II Corps under command of Horace Smith-Dorrien.^[13] The British Indian Army was called upon for assistance and in August 1914, of the 9,610 British officers initially sent to France, 20 percent were from the Indian army and of the 76,450 other ranks, 16 percent were from the Indian Army.^[13]

The German Emperor Kaiser Wilhelm was famously dismissive of the BEF, on 19 August issuing his order to "exterminate...the treacherous English and walk over General French's contemptible little army" — in later years the survivors of the regular army dubbed themselves "The Old Contemptibles". By the end of 1914, after the battles of Mons, Le Cateau, the Aisne and Ypres, the old regular British Army had been effectively wiped out, but had managed to stop the German advance.^[13]

In October 1914, the 7th Division arrived in France forming the basis of the Britiish III Corps, and the cavalry had grown into its own Corps of three divisions.^[8]

In December 1914, the BEF had expanded and now fielded five Army Corps divided between the First Army and the Second Army.^[14]

As the regular Army's strength declined, the numbers were made up, first by the Territorial force, followed by the volunteers of Field Marshal Kitchener's, New Army.^[8] By the end of August 1914, he had raised six new divisions and by March 1915, the number of divisions had increased to twenty nine.^[8] The Territorial Force was also expanded, raising second- and third-line battalions and forming eight new divisions in addition to its peacetime strength of fourteen.^[8]

A prominent feature of the early months of volunteering was the formation of Pals battalions, which in some cases formed complete brigades like the Tyneside Scottish and Tyneside Irish brigades.^[15] These were whole units that were recruited from the same town or workplace, such as the Football Battalion that became part of the Middlesex Regiment and was formed from professional footballers.^[16] Many of these pals who had lived and worked together, joined up and trained together and were allocated to the same units. As a result of the way in which they were composed of men from the same communities, when these units were committed to battle on the first day on the Somme, the heavy casualties that they suffered in many ways served to compound the effect of their losses in the towns that they had come from in Britain.^[8]

The Third Army was formed in July 1915, and with the influx of troops from Kitchener's volunteers and further reorganization the Fourth Army and the Reserve Army which became the Fifth Army were formed in 1916.^[8]

In the early stages of the war, many men, fuelled by promises of glory, decided to "join up" to the armed forces. the Army increased the number of battalions to cope with the influx of volunteers, most new infantry battalions were raised within existing regiments; the Northumberland Fusiliers were most prolific, fielding fifty one battalions, by the end of the war.^[17] However, some new regiments were created, such as the fifth regiment of the Foot Guards, the Welsh Guards, which was created in 1915 in order to complete the national complement of regiments of Foot Guards identified with the countries of the United Kingdom.^[18]

In August 1914, 300,000 men had signed up to fight and another 450,000 by the end of September.^[19] Recruitment remained fairly steady through 1914 and early 1915, but fell dramatically during the later years, especially after the Somme campaign, which resulted in 360,000 casualties.^[20] As a result, conscription was introduced in January 1916, for single men, and extended in May to all men aged eighteen to forty one.^[21] The Military Service Act of March 1916 specified that men from the ages of eighteen to forty one were liable to be called up for service in the army unless they were married (or widowed with children), or else served in one of a number of reserved professions (usually industrial but which also included clergymen and teachers). This legislation did not apply to Ireland, despite its then status as part of the United Kingdom (but see Conscription Crisis of 1918).^[22]

The conscription legislation also introduced the right to refuse military service, allowing for conscientious objectors to be absolutely exempted, to perform alternative civilian service, or to serve as a non-combatant in the army, according to the extent to which they could convince a Military Service Tribunal of the quality of their objection. Around 16,000 men were recorded as conscientious objectors,^[23] with Quakers, traditionally pacifist, playing a large role: 4,500 objectors were sent to work on farms which was deemed 'work of national importance',^[22] 7,000 were ordered non-combatant duties as stretcher bearers, but 6,000 were forced into the army, and when they refused orders, they were sent to prison;^[22] thirty-five were formally sentenced to death but immediately reprieved.^[22] Of those conscientious objectors sentenced to a term in prison; ten died while in prison and over sixty died afterwards as a result of the way they had been treated.^[22] Conscientious objectors who were deemed not to have made any useful contribution were disenfranchised for five years after the war.^[24]

By January 1916 when conscription was introduced, 2.6 million men had volunteered for service and a further 2.3 million were conscripted before the end of the war and by the end of 1918, the army had reached its peak strength of 4 million men.^[8]

Women also volunteered for service and served in a non combatant role and by the end of the war 80,000 had volunteered.^[25] They mostly served as nurses in the Queen Alexandra’s Imperial Military Nursing Service (QAIMNS), the First Aid Nursing Yeomanry (FANY), the Voluntary Aid Detachment (VAD) and from 1917, in the army when the Queen Mary's Army Auxiliary Corps (WAAC) was founded.^[26] The WAAC was divided into four sections: Cookery; Mechanical; Clerical and Miscellaneous, most stayed on the Home Front but around 9,000 served in France.^[26]

In 1914, no British officer had controlled a force larger than a division on active operations, and there were no established procedures or relevant experience to guide them in their decisions.^[27]

The first Commander in Chief of the British Expeditionary Force (BEF) appointed in August 1914, was Field Marshal John French,^[28] His last active command had been the cavalry division in the Second Boer War.^[28] As the commander in chief French's authority amongst the officer corps had been undermined by his participation in the Curragh mutiny in March 1914, when several officers threatened to resign rather then obey their orders to enforce home rule in Ireland, he became involved trying to get them to reconsider and promised Government support without the authority to do so and he later had to retract the promise and offered to resign.^[29] While his career survived the incident the army entered the war with a commander who had never commanded anything larger than a division and a potential lack of authority over his junior officers.^[30]

Of the two Corps commanders at the beginning of the war, French had remarked in 1912, that Douglas Haig the commander of the British I Corps would be better suited for a position on the staff then a field command.^[31] Like French Haig was a cavalry man and his last active command had been a cavalry brigade, in the cavalry division during the Second Boer War.^[32] The commander of the British II Corps; Horace Smith-Dorrien had began his military career in the Zulu War in 1879, one of only five officers to survive the Battle of Isandlwana^[33] He had built a formidable reputation as an infantry commander during the Sudan Campaign and the Second Boer War.^[34] After the Second Boer war he was responsible for a number of reforms notably forcing an increase in dismounted training for the cavalry, which was met by hostility by French (as a cavalry man) and by 1914, French's dislike for Smith-Dorrien was well known within the army.^[35] His was appointed Corps commander by Lord Kitchener, against the wishes of French, who had wanted to appoint his own man.^[35] Smith-Dorrien also faced problems with his fellow Corps commander Haig, who like French also disapproved of his treatment of the cavalry and was jealous of him professionally being the senior ranking officer and possibly above Haig in line as the future commander of the BEF.^[35]

French was eventually replaced in 1915, by Douglas Haig, who then became most famous for his role as commander of the BEF during the Battle of the Somme, the 3rd Battle of Ypres and the series of victories leading to the German surrender in 1918.^[36]

General Henry Rawlinson served on Kitchener's staff during the advance on Omdurman in 1898, and served with distinction in the Second Boer War, where he earned a reputation as one of the most able British commander.^[37] He commanded the 3rd Division from1910 to 1914. Rawlinson took command of the British IV Corps, in 1915 and then command of the Fourth Army in 1916 as the plans for the Allied offensive on the Somme were being developed.^[37] During the war, Rawlinson was noted for his willingness to use innovative tactics which he employed during the Battle of Amiens, where he combined attacks by tanks with the infantry.^[38]

General Hubert Gough commanded a mounted infantry regiment with distinction during the Relief of Ladysmith, but then his command was destroyed attacking a larger Boer force in 1901.^[39] He was the Brigadier in command of the 3rd Cavalry Brigade during the Curragh mutiny in March 1914.^[40] He joined the BEF in command of the 3rd Cavalry Brigade and was promoted from brigade to corps command in less then a year, in September 1914, he was given command of the 2nd Cavalry Division, in April 1915, the 7th Division and the British I Corps in July 1915, which he commanded during the Battle of Loos.^[41] In May 1916, he was appointed commander of the Fifth Army, which suffered heavy losses in the Battle of Passchendaele.^[41] The collapse of the Fifth Army was blamed for the German breakthrough in the Spring Offensive and he was dismissed as its commander in March 1918.^[41]

Away from the Western Front, General Edmund Allenby was the the commander of the Third Army on the western front before he was given command of the Egyptian Expeditionary Force during the conquest of Palestine and Syria in 1917 and 1918.^[42] He had previously served in the Zulu War, the Sudan campaign, the Second Boer war and was commander of the cavalry division on the western front, where his leadership was noted during the Retreat from Mons and the First Battle of Ypres.^{[43][44] [45]}

On the Macedonian front General George Milne commanded the British Salonika Army^[46] and General Ian Hamilton commanded the ill fated Mediterranean Expeditionary Force (MEF) during the Gallipoli Campaign.^[47] He had previously seen service in the First Boer War, the Sudan campaign and the Second Boer War.^[48]

One successful general associated with the Gallipoli campaign was General Julian Byng, Byng had started the war as the commander of the 3rd Cavalry Division after performing well during the First Battle of Ypres, he was given command of the Cavalry Corps. He was sent to the Dardenelles in August 1915, to command the British IX Corps. He arrived too late to effect the fighting, but planned the highly successful evacuation of 105,000 Allied troops and the majority of the equipment of the MEF. The withdrawal was successfully completed in January 1916, without the loss of a single man.^[49] Byng had already returned to the western front and was given command of the Canadian Corps, his most successful campaign was during the Battle of Vimy Ridge in April 1917, carried out by the Canadian Corps with British support.^[49]

One other notable commander was General Herbert Plumer, who oversaw the Second Army's overwhelming victory over the German Army at the Battle of Messines in Flanders in 1917.^[50] Plummer is generally recognised as one of the most effective of the senior British commanders on the Western Front.^[49] He earned the nickname Daddy by his meticulous planning, technical ability and constant concern for casualties.^[49]

Back in Britain the the professional commander of the British Army or Chief of the Imperial General Staff (CIGS) during the early years of the war was General James Murray,^[51] He was replaced as CIGS from 1916 by Field Marshal William Robertson, who was the first soldier in the British Army to rise from private to Field Marshal.^[51] Robertson was replaced in 1918, by Field Marshal Henry Hughes Wilson.^[52]

In August 1914, there were 28,060 officers in the British Army, 12,738 were regular officers the rest in the reserves.^[53] The number of officers in the army had increased to 164,255 by November 1918, these were the survivors from 247,061 officers who had been granted a commission during the war.^[54]

Most pre war officers came from families with military connections, the gentry, the peerage and a public school education was almost essential.^[55] In 1913, about two percent of regular officers had been promoted from the ranks.^[56] The officer corps during the war consisted of Regular officers from the peacetime army, officers who had been granted permanent commissions during the war, officers who had been granted temporary commissions for the duration of the war, territorial army officers commissioned during peacetime, officers commissioned from the ranks of the pre war regular and territorial army and temporary officers commissioned from the ranks for the duration of the war only.^[57]

In September 1914, Lord Kitchener announced that he was looking for volunteers and regular NCO's to provide the officers for the expanding army.^[57] Most of the volunteers came from the middle class, with the largest group from commercial and clerical occupations (27 percent), followed by teachers and students (18 percent) and professional men (15 percent).^[58] In March 1915, it was discovered that 12,290 men serving in the ranks had been members of a university or public school Officers' Training Corps (OTC), most applied for and were granted commissions and others who did not apply were also commissioned.^[59] At the end of 1915, the army introduced a new system for recruiting officers that ensured the vast majority had served in the ranks.^[60]

Once selected as an officer promotion could be rapid. A. S. Smeltzer, after serving in the Regular Army for fifteen years, was commissioned as a Second Lieutenant in 1915. He rose in rank, and by the Spring of 1917 had been promoted to Lieutenant Colonel and commanding officer of the 6th Battalion The Buffs (Royal East Kent Regiment).^[61] Along with rapid promotion the war also noticeably lowered the age of battalion commanding officers. In 1914, they were aged over fifty, while the average age for a battalion commanding officer in the BEF between 1917–1918, was twenty eight.^[62]

The war also provided opportunities for advancement onto the General Staff, especially in the early days of the war when many former senior officers were recalled from retirement. Some of these were found wanting due to their advanced age, their unwillingness to serve, or a lack of competence and fitness. Most were sent back into retirement before the first year of the war was over, leaving a gap that had to be filled by lower ranking officers.^[49] During the course of the war, seventy eight British and Dominion officers of the rank of Brigadier-General and above were killed on active service and another 146 were wounded.^[63]

The British official historian Brigadier James Edward Edmonds recorded in 1925 that "The British Army of 1914, was the best trained best equipped and best organized British Army ever sent to war".^[64] This was in part due to to the Haldane reforms and the Army itself recognising the need for change and training, this began with individual training in winter followed by squadron, company or battery training in spring and regimental, battalion and brigade training in summer and in late summer and autumn division or inter divisional exercises and army manoeuvre's.^[65] The Second Boer War had taught the army the dangers posed by fire zones covered by long range magazine fed rifles.^[65] In the place of volley firing and frontal attacks, there was a greater emphasis on advancing in extended order, the use of available cover, how to use Artillery to support the attack, flank and converging attacks and fire and movement.^[65] The Army expected units to advance as far as possible in a firing line without opening fire both to conceal its position and conserve ammunition, then attacking in successive waves, closing with the enemy in a decisive attack.^[65] The cavalry practised reconnaissance and fighting dismounted more regularly and the artillery no longer worked independently but were taught to support the infantry to ensure a successful attack.^[65]

The Army concentrated on rifle practice with days spent at the rifle ranges with the object of improving marksmanship and obtaining a rate of fire of fifteen rounds a minute at 300 yards (270 m), one Sergeant set the record of 38 rounds into a 12 inches (300 mm) target set at 300 yards (270 m) in 30 seconds.^[66] In their 1914 skill at arms meeting the 1st Battalion, Black Watch recorded they had: 184 marksmen, 263 first class shots, 89 second class shots and 4 third class shots, at ranges from 300 yards out to 600 yards (550 m).^[67] The infantry also practised squad and section attacks, fire from cover and often without orders from officers or NCO's so soldiers would be able to act on their own initiative.^[68] In the last exercise before the war it was noted that the infantry made wonderful use of ground, advances in short rushes and always at the double and almost invariably fires from a prone position.^[68]

After the race to the sea, manoeuvre warfare gave way to trench warfare, which the British had not prepared for expecting an offensive mobile war they had not instructed their troops in defensive tactics and had failed to obtain stocks of barbed wire, hand grenades or trench mortars.^[69] The British commanders enforced the policy that the front line was the point of farthermost advance, regardless of the terrain, fields of fire, obstacles or observation, they were also ordered by Field Marshall French that any ground gained must be held at all costs and if any ground was lost there must be an immediate counter attack.^[69]

The artillery batteries were dug in to the rear of the line and targets identified, which included forming up points and German artillery positions.^[69] When an offensive was planned the assault divisions practised manoeuvre warfare behind the lines and the cavalry regiments were retained nearby in the expectation of a breakthrough.^[70]

In the early years of trench warfare the normal infantry attack formation was based on the battalion, of four companies of four platoons each.^[71] The battalion would form ten waves with 100 yards (91 m) between each wave, each company formed two waves of two platoons, the first six waves were the fighting waves from three of the battalions companies, the seventh wave contained the battalion headquarters, the remaining company formed the eighth and ninth waves, which were carrying waves expected to carry equipment forward and the tenth wave contained the stretcher bearers and medics.^[71] The formation was expected to move forward at the rate of 100 yards (91 m) every two minutes, each man carried his rifle, bayonet, gas mask, ammunition, two hand grenades, wire cutters, a spade, two empty sandbags and flares.^[71] The carrying platoons in addition to the above also carried extra ammunition, barbed wire and construction materials to effect repairs to captured lines and fortifications.^[71]

By 1918, experience had led to a change in tactics, the infantry no longer advanced in rigid lines, but formed a series of flexible waves.^[72] They would move covertly under the cover of darkness and occupy shell holes or other cover near to the German line. Skirmishers formed the first wave and followed the creeping barrage into the German front line to hunt out points of resistance. The second or main wave followed in platoons or sections in single file. The third was formed from small groups of reinforcements and the fourth wave was expected to defend the captured territory.^[72] All waves were expected to take advantage of the ground during the advance.^[72] (see below for when operating with tanks)

Each platoon now had a Lewis gun section, a section that specialised in throwing hand grenades and each section had to provide two scouts to carry out reconnaissance duties.^[73] Each platoon was expected to provide mutual fire support, in the attack they were to advance without halting but leap frogging was accepted with the lead platoon taking an objective and the following platoons passing through them and onto the next objective, with the Lewis gunners providing fire support.^[73] Grenades were used for clearing trenches and each battalion carried forward two trench mortars to provide fire support.^[73]

The tank was designed to break the deadlock of trench warfare.^[74] In their fist battle on the Somme they were placed under command of the infantry and ordered to attack their given targets in groups or pairs, they were also given small groups of troops as an escort and to provide close defence against enemy attacks.^[75] Only nine tanks reached the German lines to engage machine gun emplacements and troop concentrations, on the way fourteen had broken down or were ditched and another ten were damaged by enemy fire.^[75] In 1917, during the Battle of Cambrai the Tank Corps adopted new tactics, three tanks working together would advance in a triangle formation with the two rear tanks providing cover for an infantry platoon.^[75] The tanks were to create gaps in the barbed wire for the following infantry to pass through, then use their armament to suppress the German strong points.^[76] The effectiveness of tank–infantry cooperation was demonstrated during the battle, when Major General George Montague Harper of the 51st (Highland) Division refused to cooperate with the tanks and they went forward without any infantry support , resulting in the destruction of more then a dozen tanks by German artillery sighted behind bunkers.^[77] Tactics had changed again by 1918, when tank attacks would have one tank every 100 yards (91 m) or 200 yards with a tank company of twelve to sixteen tanks per objective, one section of each company would be out in front, with the remainder of the company following behind and each tank providing protection for an infantry platoon, who were instructed to advance making use of available cover and supported by machine gun fire.^[78] When the tanks come across a enemy strong point they would engage the defenders forcing them into shelter, for the following infantry to deal with.^[78]

Until 1914, artillery usually fired over open sights at visible targets, and the largest unit accustomed to firing at a single target was the artillery regiment or brigade.^[79] One innovation brought about by the adoption of trench warfare was the barrage, the term was first used in the orders for the battle of Neuve Chapelle in 1915.^[79] Trench warfare had led to the necessity for indirect fire through the use of observers, more sophisticated artillery fire plans and an increasingly scientific approach to gunnery, where artillerymen had to use increasingly complicated calculations to lay the guns. Individual guns were aimed so that their fall of shot was coordinated with others to form a pattern, in the case of a barrage, the pattern was a line.^[79]

The creeping barrage was a barrage that lifted in small increments, perhaps 50 yards (46 m), so that it moved forward slowly, keeping pace with the infantry,^[80] who were trained to follow close behind the moving wall of their own fire, often as close as 55 yards (50 m), infantry commanders were encouraged to keep their troops as close to the barrage as possible, even at the risk of casualties from friendly fire.^[81][82] A creeping barrage could maintain the element of surprise, with the guns opening fire only shortly before the assault troops moved off. It was useful when enemy positions had not been thoroughly reconnoitred, as it did not depend on identifying individual targets in advance^[83] The idea behind the creeping barrage was the infantry should be into the enemy positions before the defenders had time to recover, emerge from shelters and man their firing positions.^[83] On the first day of the battle of the Somme, the barrage outpaced the infantry, allowing the defenders to recover and emerge from their dugouts, with disastrous results for the attackers.^[84] Another problem with the creeping barrage was the infantry was subordinated to the artillery schedule and the infantry commanders had less control of the tactical situation and were in danger of forgetting how to manoeuvre their troops around the battlefield.^[85] Once the infantry had reached the German trenches the artillery changed from the creeping barrage to the Box barrage, three or four barrages formed a box or more often three sides of a box around a position to isolate and prevent reinforcements being brought up into the front line.^[86] The creeping barrage showed how effective it was a year later in 1917, during the Battle of Arras.^[87] With the introduction of the Tank the artillery was no longer required to aid the infantry by destroying obstacles and machine gun positions, they instead assisted by destroying the German artillery with Counter battery fire and engage any infantry force that had escaped the attention of the tanks.^[88] By the end of the war it was realised that the important effect of the barrage was to demoralise and suppress the enemy, rather than physical destruction; a short, intense bombardment immediately followed by an infantry assault was more effective than the weeks of grinding bombardment used in 1916.^[84] The importance of the barrage was such that traditional infantry tactics, such as reliance on the infantry's own fire power to support its movement forward, was sometimes forgotten.^[89]

The Royal Engineers Signal Service was formed in 1912, and given responsibility for communications which included signal dispatch, telegraph, telephone and later wireless communications, from army headquarters to brigade and down to battery level for the artillery.^[90]

For most of the war the army primary method of communication was by signal dispatch (runner, horseback, dogs and carrier pigeon), visual signalling (flags, lamps and heliograph), telegraph and telephone.^[90]

At the start of the war the army had a small number of wireless sets, which were heavy and unreliable and operated on longwave. In 1915, trench wireless sets were used but the transmission's were easily intercepted by the listening Germans.^[90]

Civilian telephones were used at the start of the war but found to be unreliable in the damp muddy conditions, so the field telephone was designed, it operated with its own switchboard. As well as voice communication it had a a buzzer unit and with a Morse code key so it could be used to send and receive morse as well, this facility proved useful when under bombardment and the exploding shells drowned out voice communication. The telephones were connected by telephone lines which was constantly being damaged by shell fire and movement of troops.^[90]

The main types of visual signalling were flags, lamps and lights, and the heliograph. In open warfare visual signalling was the norm, making use of signal flags (a competent signaller could transmit twelve words a minute with signal flags) and the heliograph, during daylight and signal lights in darkness (signal lights were in a wooden case and used a battery operated morse code key).^[90] The problem with all these methods in trench warfare was the operator had to expose himself to enemy fire and in the case of signal lights while the the message to the rear could not be seen the reply was easily seen and again exposed the operator to enemy fire.^[90]

The Army also trained animals for use in the trenches, dogs were trained to carry messages and horses, mules and dogs were all used to lay telephone and telegraph cables.^[90] Pigeons were also used to carry messages back from the front line and were also carried in tanks to send message back during an attack.^[90] Over 20,0000 pigeons and 370 handlers were used during the war and at times found to be the only means of communication.^[90]

At the start of the war the Royal Flying Corps (RFC), commanded by Hugh Trenchard consisted of five squadrons – one observation balloon squadron (RFC No 1 Squadron) and four aeroplane squadrons (RFC No 2, No 3, No 4 and No 5 Squadrons).^[91] These were first used for aerial spotting on 13 September 1914, but only became efficient when they perfected the use of wireless communication at Aubers Ridge on 9 May 1915. Aerial photography was attempted during 1914, but again only became effective the next year. By 1918, photographic images could be taken from 15,000 feet, and interpreted by over 3,000 personnel. Planes did not carry parachutes until 1918, though they had been available since before the war.^[92]

On 17 August 1917, General Jan Smuts presented a report to the War Council on the future of air power. Because of its potential for the 'devastation of enemy lands and the destruction of industrial and populous centres on a vast scale', he recommended a new air service be formed that would be on a level with the Army and Royal Navy. The formation of the new service however would make the under utilised men and machines of the Royal Naval Air Service (RNAS) available for action across the Western Front, as well as ending the inter-service rivalries that at times had adversely affected aircraft procurement. On 1 April 1918, the RFC and the RNAS were amalgamated to form a new service, the Royal Air Force (RAF). The RAF was under the control of the new Air Ministry. After starting in 1914 with some 2,073 personnel, by the start of 1919 the RAF had 4,000 combat aircraft and 114,000 personnel.^[93]

In September 1915, the Machine Gun Corps was formed to provide heavy machine gun teams, after a definite proposal was made to the War Office for the formation of a single specialist Machine Gun Company per infantry brigade, by withdrawing the guns and gun teams from the battalions.^[94] The Machine Gun Corps (MCG) was created in October 1915, it consisted of infantry Machine gun companies, cavalry machine gun squadrons and motor machine gun batteries.^[94] In the trenches the Corps guns were deployed with an interlocking field of fire and were devastating defensive weapon against attacking infantry.^[94] They were also used offensively to fire an indirect barrage over the heads,^[94] and from the flanks,^[95] of the advancing infantry and behind the German trenches, to stop reinforcements and supplies getting to the front.^[94]

The Army Service Corps (ASC) operated the transport system to deliver men, ammunition and materials to the front. From 12,000 men at the start of the war the Corps increased in size to over 3,000,000 by November 1918.^[96] In addition they had under command Indian, Egyptian, Chinese and other native labourers, carriers and stores men.^[96] They provided horsed transport companies, mechanical transport companies, the army remounts service and ASC Labour companies.^[96] In August 1914, they delivered 4,500,00 pounds of bread, to the front which had increased to 90,000,000 pounds by November 1918.^[96]

The Royal Army Medical Corps (RAMC) supplied the Doctors, casualty evacuation, field ambulances and hospitals for the army.^[97] The Corps was assisted in its work by voluntary help from the British Red Cross, St John's Ambulance and the Friends Ambulance Unit.^[97] The only person to be awarded the Victoria Cross twice during the war was a Doctor in the RAMC, Captain Noel Godfrey Chavasse, VC and Bar, MC.^[98]

The most important theatre for the British Army was the Western Front but the British Army fought in almost every theatre of the World War I. In the four years of the war, the British Army suffered nearly 2.5 million casualties; 662,000 men killed, 140,000 missing and 1,650,000 wounded.^[99]

Under the command of Field Marshal Sir John French,^[28] the British Expeditionary Force (BEF) began to deploy to France within days of the declaration of war.^[100] The first encounter with the Germans came at Mons on 23 August 1914,^[100] after which the Allies began the Great Retreat, during which the BEF is involved in the Battle of Le Cateau.^[101] The BEF had small role in halting the German advance at the Marne,^[102] before participating in the Aisne counter-offensive,^[103] in September which was followed by a period known as the "Race to the Sea" during which the BEF redeployed to Flanders.^[104] For the BEF, 1914 ended with "First Ypres" which marked the beginning of a long struggle for the Ypres salient.^[105] British casualties in the fighting between 14 October and 30 November were 58,155 (7,960 dead, 29,562 wounded and 17,873 missing). It is often said that the pre war professional army died at the first battle of Ypres. The army had arrived in France with 84,000 infantry. By the end of the battle of Ypres, the BEF had suffered 86,237 casualties, mostly to the infantry. ^[105]

Trench warfare prevailed in 1915 and the BEF, as the junior partner on the Western Front, fought a series of small battles, at times coordinated with the larger French offensives; in the Battle of Neuve Chapelle in March,^[106] Aubers Ridge and Festubert in May and during the Battle of Givenchy in June.^[107][108] On 22 April 1915, the Germans launched the Second Battle of Ypres, employing poison gas for the first time on the Western Front and capturing much of the high ground that ringed the salient.^[109] By September 1915 the British Army had grown in strength, with the first New Army divisions entering the line, and as part of the Third Battle of Artois,^[110] the Army launched a major attack the Battle of Loos utilising their own newly developed chemical weapons for the first time.^[111] The result was another costly and disappointing failure and marked the end for Field Marshal French; on 19 December 1915, General Sir Douglas Haig became Commander of the BEF.^[36]

For the British Army, 1916 was dominated by the Battle of the Somme which started disastrously on 1 July. The Somme offensive was intended to achieve a decisive victory for the British and French Allies over the Germans on the Western Front after 18 months of trench deadlock.^[112] The first day on the Somme remains the bloodiest day in the history of the British Army when over 19,000 soldiers were killed and a nearly 40,000 were wounded, all for little or no gain.^[113] The only real British success was in the south where, using imaginative tactics and helped by the French artillery, the 18th (Eastern) Division and 30th Division took all their objectives, including Montauban, and the 7th Division captured Mametz.^[113] At Thiepval the 36th (Ulster) Division seized the Schwaben Redoubt but was forced to withdraw because of lack of progress elsewhere.^[113] There followed nearly five months of attrition during which the Fourth Army of General Henry Rawlinson and the Fifth Army of General Hubert Gough advanced about five miles (8 km) for a cost of 420,000 casualties.^[114]

In February 1917 the German Army began to withdraw to the Hindenburg Line and it was these formidable defences that elements of the British Army assaulted in the Battle of Arras in April. For this battle, the British Prime Minister, David Lloyd George, had placed Haig and the BEF under the orders of new French Commander-in-Chief, Robert Nivelle who planned a major French Army offensive in Champagne.^[115] When the battle officially ended on 16 May, British Empire troops had made significant advances, but had been unable to achieve a major breakthrough at any point.^[115] Having failed to deliver a breakthrough and Haig, freed from the restraints of the French command, now embarked on his favoured plan to launch an offensive in Flanders. In a successful preliminary operation, General Herbert Plumer's Second Army seized the Messines Ridge south of Ypres.^[116] The Third Battle of Ypres, which began on 31 July 1917, was one of the worst ordeals endured by British and Dominion forces during the war, with the battlefield reduced to a quagmire. It was not until 6 November that the Passchendaele ridge was captured, by which time the British Army had sustained 310,000 casualties.^[117]

For the British Army, 1917 ended with faint promise in the Battle of Cambrai which demonstrated the potential of tanks operating en masse. Third Army commander, General Julian Byng, planned an ambitious breakthrough and achieved an unprecedented advanced of six kilometres on the first day but lacked the reserves to either continue or consolidate. A German counter-offensive succeeded in recapturing most of the lost ground.^[118]

The year 1918 started with disaster and ended in triumph for the British Army. On 21 March 1918, German commander, General Erich Ludendorff, launched the Spring Offensive and the main weight of the first blow, Operation Michael, fell on the British Fifth Army of General Gough which was forced into retreat, finally halting the German advance on the Marne in June 1918.^[119] The next German attack came south of Ypres in the Battle of the Lys river and here too the British Army fell back. Haig issued his famous Order of the Day, "With our backs to the wall and believing in the justice of our cause, each one of us must fight on to the end." In response to the crisis facing the Allies, French general Ferdinand Foch was made Supreme Commander for Allied forces on the Western Front, placing the BEF under his strategic direction.^[120][121]

On 8 August 1918, General Rawlinson's Fourth Army launched the Battle of Amiens which marked the start of the Hundred Days Offensive, the final Allied offensive on the Western Front. Over the following weeks, all five armies of the BEF went on the offensive from the Somme to Flanders.^[122] Fighting continued right up until the Armistice with Germany came into effect at 11.00 am on 11 November 1918.^[123]

In the process, the BEF took 188,700 prisoners and 2,840 guns which was only 7,800 prisoners and 935 guns less than those taken by the ,French, Belgian and American armies combined.^[63]

The British Army was involved in some comparatively obscure theatres of the war such as the symbolic contribution of the 2nd Battalion South Wales Borderers in support of Japanese forces in the capture of the German port of Tsingtao in China in 1914, in what became known as the Siege of Tsingtao.^[124] The British were part of a 23,0000 strong task force which included a mixed British–Indian Brigade of 1,500 troops and the British battleship, HMS Triumph. A bombardment of the port started on the 31 October 1914, and by the 7 November 1914, the Japanese 18th Division and 29th Infantry Brigade, and the British–Indian Brigade, stormed and captured the garrison and its 4,000 troops.^[125]

A few British Army battalions also participated in the East African Campaign against von Lettow-Vorbeck's elusive German and African askari forces, however most British operations in Africa were carried out by African askari units such as the King's African Rifles (KAR), or South African or Indian Army units. The British force the 1st East African Division was led in turn by the British General Horace Smith-Dorrien, South African General Jan Smuts and British General Arthur Reginald Hoskins.^[125][126] The force was made up from units of the KAR and the 27th Bangalore Brigade from the British Indian Army with the 2nd Battalion, Loyal Regiment (North Lancashire) under command. The German forces of von Lettow-Vorbeck's Schutztruppe remained undefeated and surrendered on the 25 November 1918, 14 days after the Armistice in Europe.^[125]

The casualty rate amongst British and Empire troops, excluding the Africans, was 6,000 dead and 3,000 wounded. More troops died from diseases than from enemy action and illness accounted for 70 percent of the total casualties.^[125]

Turkey had entered the war on the side of the Germans on 31 October 1914. One its first acts was to close the Dardanelles Straits to the Allies.^[125] In April 1915, following the failure of the Royal Navy's attempt capture the Dardanelles, the British and ANZAC forces landed on the Gallipoli peninsula, under the command of General Ian Hamilton.^[125] The main British attacks were the first, second and the Third Battle of Krithia. These were a series of attacks against the Turkish defences aimed at capturing the original objectives of 25 April, 1915. They all failed to achieve their objectives.^[127]

In August another landing was made at Suvla Bay The Suvla landing was reinforced by the arrival of the 10th, the 53rd and the 54th Divisions from Kitchener's New Army plus the dismounted yeomanry of the 2nd Mounted Division.^[125] The 29th Division was also moved from Helles to Suvla for one more push. The final British attempt to resuscitate the offensive came on 21 August with attacks at Scimitar Hill and Hill 60. Control of these hills would have united the Anzac and Suvla fronts but neither battle achieved success. When fighting at Hill 60 ceased on 29 August, the battle for the Sari Bair heights, and indeed the battle for the peninsula, was effectively over and by January 1916, the Allies had withdrawn.^[125]

Estimates of casualties vary enormously, but of the around 480,000 Allied troops involved in the campaign, 180,000 were wounded and 44,000 died, 20,000 of the dead being British.^[125]

A new front was opened in Salonika at the request of the Greek government, intending to support Serbian forces and oppose Bulgaria. The first troops of the British Salonika Army arrived in Salonika in October 1916, too late to prevent the Serbian Army from retreating into Albania and Greece. French, British and Russian troops arrived in Salonika between 1916 and 1917 and became known as the Army of the East or the Army of the Orient, under the overall command of French General Maurice Sarrail.^[128] With the objective of destroying the Bulgarian Army, the French and British launched a new offensives in April 1917, without any significant success. A stalemate ensued without any movement by either side and the front became known as Europe's biggest interment camp for the Allies by the Germans.^[125] This situation lasted until 18 September 1918, when the British and Greek Armies, under the command of General George Milne attacked in the Lake Dorian Sector.^[125] The Bulgarian Army, now in retreat signed an armistice on the 30 September 1918.^[125]

Italy joined the war on the Allies side on 5 May 1915, declaring war on Austria-Hungary on 23 May 1915, and on Germany on 28 August 1916.^[125] The British army's involvement in the Italian campaign started much later, however, in late 1917, when they were sent to help prevent a collapse on the Italian front. On 24 October 1917 in the Battle of Caporetto the Second Italian Army collapsed and the Italians were forced to retreat to the Piave River, where they could be reinforced with five British Divisions and six French Divisions from the Western Front, complete with supporting arms and commanded by General Herbert Plumer.^[125] The reinforced Italians the successfully managed to halt the Austro-Hungarian advance at the Battle of the Piave River.^[125] During the Allied counter attack in October 1918, the Austro-Hungarian Army collapsed after taking heavy losses at the Battle of Vittorio Veneto. An armisticec was signed shortly after on 3 November 1918.^[125]

The Sinai and Palestine Campaign, grew out of criticism of the policy of a static defence of the Suez canal which called on the services of six infantry divisions and five mounted brigades.^[129] After the Turkish First Suez Offensive and their subsequent defeats in the Battle of Romani, the Battle of Magdhaba and the Battle of Rafa. The British Army, which included the 42nd, 52nd, 53rd, 54th, 74th and the 75th Divisions from the infantry and the mounted units were the Yeomanry Mounted Division, the Australian Light Horse and the New Zealand Mounted Rifles Brigade, under the command of General Archibald Murray made steady progress against Ottoman opposition until the First and Second Battle of Gaza in 1917, which were decisive Turkish victories.^[130] The British won the following Battle of El Buggar Ridge The failure of Murray to deliver a victory in the second Battle Gaza fight motivated the War Office to change the command of the Egyptian Expeditionary Force (EEF). On 28 June, 1917 General Edmund Allenby took over the command and reinvigorated the campaign, his forces now included the Desert Mounted Corps, the XX Corps and the XXI Corps, they won the Third Battle of Gaza and the Battle of Mughar Ridge, which succeeded in causing the Ottoman Seventh and Eighth Armies to withdraw towards Jerusalem and Haifa respectively.^[125] This victory and the capture of Jerusalem in December 1917 and the decisive Meggido Offensive in September 1918 precipitated an armistice with the Ottoman Empire which was signed on the 31 October 1918.^[42]

Total Allied casualties in the Sinai and Palestine campaign were 60,000 of which 20,000 were killed, 15,000 of the dead were British.^[125]

The British army force fighting in Mesopotamia was principally drawn from the British Indian Army, with only one solely British formation, the 13th (Western) Division. The Army was highly dependent upon Indian forces, its objective was to watch over the Royal Navy's oil supply from Persia. On the 7 November 1914, the British Indian force, led by General Sir John Nixon, invaded Mesopotamia and on the 23 November entered Basrah.^[125] After this initial there followed a disastrous and humiliating defeat of the British by the Turks at the Siege of Kut-al-Amara from the 7 December 1915 to 29 April 1916, when the entire garrison of 13,000 British and Indian troops surrendered.^[125] The British reorganised and raised the number of available troops to 250,000.^[125] The British eventually regained momentum upon General Frederick Stanley Maude becoming commander, a new British offensive began in December 1916. On the 24 February 1917, Khut Al Amara fell to the joint British and Indian force and Baghdad was captured in March 1917.^[125] A week after the capture of Baghdad General Maude issued the Proclamation of Baghdad, which contained the famous line "our armies do not come into your cities and lands as conquerors or enemies, but as liberators".^[131] General Maude died of cholera on the 18 November 1917 and was succeeded by Lieutenant General Sir William Marshall who continued with the River War, until in October 1918, the British captured the Mosul oil fields which led to a collapse of the Turkish forces and the Armistice of Mudros with Turkey was signed on the 30 October 1918.^[125]

During the campaign there were 100,000 British and Indian casualties; of these, 53,000 died, with 13,000 of the dead dying from disease.^[125]

The Easter Rising, was an rebellion staged in Ireland during Easter Week, 1916. The rising was mounted by Irish republicans with the aims of ending British rule in Ireland and establishing an Irish Republic. Organised by the Military Council of the Irish Republican Brotherhood, the Rising lasted from Easter Monday 24 April to 30 April 1916.^[132] Members of the Irish Volunteers, joined by the smaller Irish Citizen Army, along with 200 members of Cumann na mBan, seized key locations in Dublin and proclaimed an Irish Republic independent of Britain.^[133]

Army reinforcements were moved into Dublin and by 28 April, the 1,600 rebels were facing 18 to 20,000 soldiers,^[132] the rising was suppressed after seven days of fighting, and its leaders were court martialled and executed.^[134] The Easter Rising casualties were 450 killed, 2,614 injured, and 9 missing, almost all in Dublin. The only significant action elsewhere was at Ashbourne, 10 miles (16 km) north of Dublin. Military casualties were 116 dead, 368 wounded and 9 missing, and the Irish and Dublin police forces had 16 killed and 29 wounded and 254 non combatant civilians died.^[132]

By the end of 1914 the war on the Western Front had reached stalemate and the trench lines extended from the Belgian coast to the Swiss frontier.^[135] By September 1915, the length of the British front line stretched for some 70 miles (110 km). Soldiers were in the front or reserve line trenches for about eight days at a time, before being relieved.^[135]

There were three trenches in the front line; the fire trench, the support trench and the reserve trench, all being joined by communication trenches.^[136] They varied in depth, but they were usually about four or five feet deep, with a built up wall to allow men to stand upright, the fire trenches were provided with a fire step built into the front wall, so the occupants could return fire during an attack.^[136] Ideally the bottom of the trench was lined with duck boards to prevent men from sinking into the mud and dug outs were made for living in, these gave shelter from the elements and shrapnel, but in the British Army dugouts were usually reserved for the officers and the senior Non-commissioned officers.^[136] The men were then expected to sleep wherever they could and in wet weather they lived under ground sheets or in tents on the bottom of the trench on the duck boards.^[136]

At the front soldiers were in constant danger from artillery shells, mortars and bullets and as the war progressed they also faced aerial attack.^[137] Some sectors of the front saw little activity throughout the war, making life in the trenches comparatively easy. Other sectors were in a perpetual state of violent activity. However, quiet sectors still amassed daily casualties through sniper fire, artillery fire and disease, the harsh conditions, often wet and muddy and the constant company of lice, and rats which fed on unburied bodies, often carried disease.^[135] Food was very restricted because of supply problems and disease was rife in the damp, rat infested conditions,with many troops suffering from trench foot (the infection and swelling of feet exposed to long periods of dampness and cold, sometimes leading to amputation),^[138] trench fever (an infection caused by louse faeces)^[138] and trench nephritis (an inflammation of the kidneys).^[138] They suffered frost-bite in the cold winter months and heat exhaustion in the summer and the men were frequently wet and extremely muddy, or dry and exceedingly dusty.^[135][137]

The daily routine of life in the trenches began with the morning 'stand-to. An hour before dawn everyone was roused and ordered to man their positions in order to guard against a dawn raid by the Germans.^[139] With stand-to over, it was time for the men to have breakfast, wash and go to the toilet. Once this had been completed the NCO's would assign daily chores, before attending to the cleaning of rifles and equipment, filling sandbags, repairing trenches or digging latrines.^[139] Once the daily chores had been completed the men who were off duty would find a place to sleep.^[139] Due to the constant bombardments and the sheer effort of trying to stay alive, sleep deprivation was common. Soldiers also had to take it in turns to be on sentry duty, watching for enemy movements.^[140]

Given that each side's front line was constantly under watch by snipers and lookouts during daylight, movement was therefore restricted until night fell and after the dusk stand-to.^[139] Under the cover of darkness troops attended to vital maintenance and resupply, with rations and water being brought to the front line, and fresh units swapped places with troops returning to the rear for rest and recuperation.^[139] Trench raiding was also carried out and construction parties formed to repair trenches and fortifications, while wiring parties were sent out to repair or renew the barbed wire in no man's land.^[139] Then an hour before dawn, everyone would stand-to again.^[139]

There was a set procedure for a division moving into the front line, once they had been informed they were moving forward, the brigadiers and battalion commanders would be taken to the forward areas to reconnoitre the section of the front to be occupied by their troops.^[141] While the brigadiers and battalion commanders were at the front, the battalion transport officers would be taken to the headquarters of the division they were relieving to see the methods used for drawing rations and ammunition and how they were supplied to the troops at the front at the same time detachments from the divisional artillery group would move forward and attached to the artillery batteries of the division they were relieving.^[141] Five days later the infantry battalions destined for the front line sent forward their specialists, from the Lewis gun teams, the grenade officer, the machine gun officer, the four company commanders and some of the signallers to take over the trench stores and settle into the trench routine before the battalions moved in.^[141] Overnight the battalions would move into the line and the artillery would take over the guns already in position, leaving theirs behind which were then taken over by the batteries that had been relieved.^[141]

The standard-issue Webley revolver at the outbreak of World War I was the Webley Mk V (adopted 9 December 1913^[142]), but there were considerably more Mk IV revolvers in service in 1914,^[143] as the initial order for 20,000 Mk V revolvers had not been completed when hostilities began.^[142] On 24 May 1915, the Webley Mk VI was adopted as the standard sidearm for British troops^[142] and remained so for the duration of World War I, being issued to officers, airmen, naval crews, boarding parties, trench raiders, machine-gun teams, and tank crews. The Mk VI proved to be a very reliable and hardy weapon, well suited to the mud and adverse conditions of trench warfare, and several accessories were developed for the Mk VI, including a bayonet (made from a converted French Pritchard bayonet),^[144] a speedloader device ("Prideaux Device"),^[145] and a stock allowing for the revolver to be converted into a carbine.^[146]

The iconic Lee-Enfield rifle, the SMLE Mk III, was introduced on 26 January 1907, along with a Pattern 1907 (P'07) Sword Bayonet and featured a simplified rear sight arrangement and a fixed, rather than a bolt-head-mounted sliding, charger guide.^[147] The fast-operating Lee bolt-action and large magazine capacity enabled a trained rifleman to fire 20 to 30 aimed rounds a minute, making the Lee-Enfield the fastest military bolt-action rifle of the day. ^[148] World War I accounts tell of British troops repelling German attackers who subsequently reported that they had encountered machine guns, when in fact it was simply a group of trained riflemen armed with SMLE Mk III rifles.^[149] During the war, the standard SMLE Mk III was found to be too complicated to manufacture (an SMLE Mk III rifle cost the British Government £3/15/-)^[150], and demand was outstripping supply, so in late 1915 the Mk III* was introduced.^[147]

The Vickers machine gun accompanied the BEF to France in 1914, and in the years that followed, proved itself to be the most reliable weapon on the battlefield, some of its feats of endurance entering military mythology.^[151] Perhaps the most incredible was the action by the 100th Company of the Machine Gun Corps at High Wood on 24 August 1916. This company had 10 Vickers guns, and it was ordered to give sustained covering fire for 12 hours onto a selected area 2,000 yards (1,800 m) away in order to prevent German troops forming up there for a counter-attack while a British attack was in progress. Two companies of infantrymen were allocated as carriers of ammunition, rations and water for the machine-gunners. Two men worked a belt-filling machine non-stop for 12 hours keeping up a supply of 250-round belts. 100 new barrels were used up, and all the water, including the men’s drinking water and contents of the latrine buckets, was used to keep the guns cool. And in that 12 hour period the 10 guns fired a million rounds between them. One team is reported to have fired 120,000 from their gun to win a five franc prize offered to the highest-scoring gun. And at the end of operation, it is alleged that every gun was working perfectly and that not one gun had broken down during the whole period. It was this reliability which endeared the Vickers to the soldiers that used it. It rarely broke down; it just kept on firing.^[151] Demand from the British Army for Vickers machine guns was so high that Vickers had to find new ways of increasing production and by 1915 Vickers had supplied the British armed forces with 2,405 guns.^[152] These increases continued throughout the war: 7,429 were supplied in 1916, 21,782 in 1917 and 39,473 in 1918.^[152]

The British officially adopted the Lewis machine gun in .303 calibre for Land and Aircraft use in October 1915.^[153] Despite costing more than a Vickers gun to manufacture (the cost of a Lewis Gun in 1915 was £165,^[150] and the Vickers cost about £100),^[154] Lewis machine-guns were in high demand with the British military during World War I. The Lewis also had the advantage of being about 80% faster (in both time and component parts) to build than the Vickers gun (and was a lot more portable),^[155] and thus orders were placed by the British Government between August 1914 and June 1915 for 3,052 Lewis guns.^[150] By the end of World War I over 50,000 Lewis Guns had been produced in the US and UK and they were nearly ubiquitous on the Western Front, outnumbering the Vickers gun by a ratio of about 3:1.^[154]

The Lewis Gun utilised two different drum magazines, one holding 47 and the other 97 round s and had a rate of fire of 500 to 6oo rounds per minute.^[156] The gun weighed 28 pounds (13 kg), only about half as much as a typical medium machine gun of the era, such as the Vickers machine gun, and was chosen in part because, being more portable than a heavy machine gun (such as the Vickers), it could be carried and used by a single soldier.^[157]

Mortars are curved trajectory weapons that can lob shells into trenches whose occupants would be unaffected by flat trajectory weapons but, compared to the standard artillery guns, mortars have a relatively short range.^[158] During the early years of the war it quickly became clear that some type of weapon was needed to provide artillery like fire support to the infantry.^[158] The Army already had rifle grenades, which were useful but they possessed insufficient range and power to serve such purposes.^[158] A weapon that was fully man transportable yet could fire reasonably powerful shells at targets beyond the range of rifle grenades was badly needed.^[158] The Stokes trench mortar was developed for precisely this purpose. The Stokes Mortar was a simple weapon, that was easy to manufacture and use.^[158] The weapon was broken down into three sections for easy transport, the barrel (tube) which weighed 43 pounds, the base plate weighed 28 pounds (13 kg) and bipod weighed 37 pounds (17 kg) for a total of 108 pounds (49 kg).^[158] The Stokes Mortar could fire as many as 25 bombs per minute and had a maximum range of 800 yards (730 m).The first recorded use of Stokes mortars by the British was near Loos, France, in September 1916, where they proved to be very valuable weapons.^[158] British Empire units had 1,636 Stokes mortars in service on the Western Front at the Armistice.^[159]

The 2-inch Medium Mortar wass designed and manufactured by the Royal Ordnance Factories in early 1915 and introduced along with the 1.57 inch mortar in March 1915. It incorporated what was known of the German prewar Krupp mortar.^[160] This was the first design to meet all the requirements, after modifications to simplify manufacture, it fired a spherical cast iron bomb of 42 pounds (19 kg) which was considered the largest practical size for use from trenches, at ranges from 100 yards (91 m) to 600 yards (550 m) using a simple 2 inches (51 mm) tube as the mortar body. Drawbacks were that the steel tail was usually projected backwards towards the firer when the bomb detonated, resulting in occasional casualties; and the No. 80 fuze was also required by the 18 pounder field guns which were given priority, limiting mortar ammunition supply to the front until early 1916, when a special cheap trench mortar fuze was developed.^[161] The 2-inch mortar served in limited numbers in France in 1915, from March, with early mortars and ammunition made by the Royal Ordnance Factory, mass production finally began with an order in August 1915, for 800 mortars from several railway workshops and agricultural machinery makers, together with an order for 675,000 bombs from numerous small firms.^[162]

The ML 9.45-inch (240 mm) mortar was a design based on the French 240 mm Trench Mortar and introduced in 1916, the British version differed from the French LT weapon in that the propellant charge was loaded through the muzzle^[163] In June 1916, following unsatisfactory trials with the French model, the army replaced them with 30 of its own model, firing a 150 pound bomb, followed by 200 more in December 1916.^[164] The 9.45 inch mortar also known as the Flying Pig was a Corps level weapon.^[165]

The advent of World War I generated new demands for strongly armored self-propelled weapons which could move powerfully on any kind of terrain, leading to the development of the tank. The great weakness of the armoured car was indeed that they required smooth terrain to move upon, and new developments were needed for cross-country capability.^[166] The Mark I tank was a British invention, in February 1915, the First Lord of the Admiralty Winston Churchill created the Landships Committee to investigate a mechanical solution to the stalemate of trench warfare.^[74] The Mark I tanks, were operated by the Heavy Branch of the Machine Gun Corps and had a range of 23 miles (37 km) without refuelling and a speed of 3 miles per hour.^[75] , the Mark I tank first saw service on the Somme in September 1916.^[167] The Mark I tank was available in two different formats called: male and female. Male tanks mounted a six pounder gun in each sponson, plus three light Hotchkiss machine guns. Female tanks had two heavy Vickers machine guns in place of the six pounders.^[74] The tank evolved during the war and by 1917, the ninth model the Mark IX tank had been designed which was different to its predecessors, in that it could carry thirty infantrymen or ten tons of cargo.^[168] The Mark IX was armed with two machine guns and had loopholes for the infantry to fire from.^[168]

Another tank in use was the Medium Mark A Whippet, while the Mark I tanks had been designed to attack the German trenches the Tank Corps now wanted a lighter, faster tank to work with the cavalry over open country.^[169] The Whippet had a crew of four and was armed with three Hotchkiss Machine Guns, they weighed 14 tons and had a road speed of just over 8 miles (13 km) per hour and a radius of 80 miles (130 km).^[169] They were very fast by 1918, standards but tank crews found them difficult to drive and combat experience showed that it was not suitable for working with the cavalry.^[169] Whippets first saw service during the German Spring Offensive in 1918, by the end of the war the Whippet was responsible for more German casualties than any other British tank of the war.^[170]

At the start of the war the only grenade in service with the army was the No 1 Grenade.^[171] Because of the problems associated with it, the Jam Tin Grenade was designed. It contained an inner can of explosive with an outer can of metal fragments or ball bearings. The fuses that were developed for the Jam Tin Grenade were activated by friction or a by lighted taper which was often replaced by a lighted cigarette.^[171] This was followed by the highly successful Mills bomb in 1915.^[171] It was oval in shape to fit into a clenched fist and time fused.^[171] The detonator was activated by a spring driven firing pin which was restrained by a lever that in turn was locked by a safety pin.^[171] The Mills bomb was a defensive grenade. After throwing the user had to take cover immediately and a competent thrower could manage 20 yards (18 m) with reasonable accuracy.^[171] Adopted as the standard grenade, over 33 million Mills bombs were produced in the final three years of the war.^[172]

The first use of poison gas on the Western Front was on 22 April 1915, by the Germans at Ypres, against Canadian and French colonial troops. The initial response was to equip troops with cotton mouth pads for protection. Soon afterwards the British introduced the Black Veil Respirator, which consisted of a long cloth which was used to tie chemical-soaked mouth pads into place.^[173] Dr. Cluny MacPherson of The Royal Newfoundland Regiment brought the idea of a mask made of chemical absorbing fabric and which fitted over the entire head to England,^[174] and this was developed into the British Hypo Helmet of June 1915. This mask offered protection to the eyes as well as to the respiratory system. One British officer described it as a smoke helmet, a greasy grey-felt bag with a tale window certainly ineffective against gas.^[173] This helmet had two celluloid eyepieces, but there was no way to expel the carbon dioxide build up inside the mask .^[173] This type of mask went through several stages of development before being superseded in 1916 by the canister gas mask the PH helmet.^[173] This had a mask connected to a tin can containing the absorbent materials by a hose and an outlet valve to reduce the carbon dioxide build up inside the mask.^[173]

The first delivery of the Brodie helmet to the British Army in 1915. Initially there were far from enough helmets to equip every man, so they were designated as "trench stores", to be kept in the front line and used by each unit that occupied the sector. It was not until the summer of 1916, when the first 1 million helmets had been produced, that they could be generally issued.^[175]

The Brodie helmet reduced casualties but was criticized by General Herbert Plumer on the grounds that it was too shallow, too reflective, its rim was too sharp, and its lining was too slippery. These criticisms were addressed in the Mark I model helmet of 1916 which had a separate folded rim, a two-part liner, and matte khaki paint finished with sand, sawdust, or crushed cork to give a dull, non-reflective appearance.^[176]

In 1914, the heaviest artillery gun was the 60 pounder gun, four in each of the heavy batteries. The Royal Horse Artillery had the 13 pounder gun and the Royal Field Artillery the 18 pounder gun.^[177] By 1918, the situation had changed and artillery were the dominant force on the battlefield.^[178] Between 1914–1918 the heavy and siege artillery of the Royal Garrison Artillery had increased from thirty two heavy and six siege batteries to 117 heavy and 401 siege batteries.^[179] With the increase in the number of batteries of heavier guns the armies need to find a more efficient method of moving the heavier guns around, (it was proving difficult to find the number of draught horses required) the War office ordered over one thousand Holts Caterpillar tractors, which transformed the mobility of the siege artillery.^[180] The army also mounted a variety of surplus naval guns, on various railway platforms to provide mobile long-range heavy artillery on the Western Front.^[181]

The 18 pounder gun was the most important field gun of the war,^[182] with over 10,000 being manufactured by the end of the war and 113,000,000 rounds of ammunition issued.^[183] Some Royal Horse Artillery batteries were also re-equipped with it as their 13 pounders proved unsuited to the prevalent trench warfare.^[182]

The 6 inch guns were first sent to France in 1915, mounted on improvised field carriages.^[184] Following its successful employment in the Battle of the Somme its role was defined as counter battery fire and also they "were most effective for neutralising defences and for wire cutting with a new fuse which reliably burst instantly above ground on even slight contact, instead of forming craters, they were also employed for long range fire against targets in depth.^[185] It was supposed to be replaced by the BL 6 inch Gun Mk XIX, 310 of which were built during the war.^[186] This model gun served in all theatres, with 108 being in service on the Western front at the end of World War I.^[187]

The 60 pounder guns were formed into "Heavy Batteries" in the First World War operated by the Royal Garrison Artillery and used mainly for counter-battery fire (i.e. suppressing or destroying the enemy's artillery). When World War I began a single four gun battery was attached to each infantry division of the BEF.^[188] From early 1915, 60 pounder batteries moved from Division to Army control.^[189] From June 1916 ,the War Office adopted Major-General Birch's recommendations to increase heavy battery sizes to six guns,^[190] as more guns with better concentration of fire power were required on the Western Front, while minimising the administrative overhead of more batteries.^[191]

Some of the largest guns deployed were the Railway guns, there were sixteen of the smaller BL 9.2 inch Railway Guns in service by the end of the war,^[192] which together fired a total of 45,000 rounds.^[193] The BL 12 inch Railway Gun, had the ability to send a 850 pounds (390 kg) shell 12 miles (19 km) into the German rear area and was used during the Battle of Arras.^[194] The largest calibre Railway gun used was the BL 14 inch Railway Gun Boche Buster, which fired its first round in the presence of King George V and scored a direct hit on the Douai railway yards 18 miles (29 km) away.^[195]

In the post war publication Statistics of the Military Effort of the British Empire During the Great War 1914–1920 (The War Office, March 1922), the official report lists 908,371 'soldiers' as being either killed in action, dying of wounds, dying as prisoners of war or missing in action in World War I. This is broken down into the United Kingdom and former colonies 704,121; Undivided India 64,449; Canada 56,639; Australia 59,330; New Zealand 16,711; South Africa 7,121.^[99]

A second publication Casualties and Medical Statistics, 1931, the final volume of the Official Medical History of the War, gives British Empire Army losses by cause of death.^[196] The total losses in combat from 1914–1918 were 876,084, which included 418,361 killed, 167,172 died of wounds, 113,173 died of disease or injury, 161,046 missing presumed dead and 16,332 died when a prisoner of war.^[196]