Prior to its uniform adoption of proportional representation in 1999, the United Kingdom used first-past-the-post for the European elections in England, Scotland and Wales. The European Parliament constituencies used under that system were smaller than the later regional constituencies and only had one Member of the European Parliament each.

From 1984 to 1999, the constituency of Merseyside West was one of them, following on from the previous "Liverpool" constituency which existed on different boundaries from 1979 to 1984.

When it was created in England in 1984, it consisted of the Westminster Parliament constituencies of Bootle, Crosby, Liverpool Broadgreen, Liverpool Mossley Hill, Liverpool Riverside, Liverpool Walton, Liverpool West Derby, Southport, and remained broadly the same, despite the internal re-arrangement of some of these constituencies (Wavertree replacing Broadgreen and Mossley Hill, and a boundary shift for some of the others).

The European Parliament (EP) is the directly elected parliamentary institution of the European Union (EU). Together with the Council of the European Union (the Council) and the European Commission, it exercises the legislative function of the EU. The Parliament is composed of 751 (previously 766) members, who represent the second largest democratic electorate in the world (after the Parliament of India) and the largest trans-national democratic electorate in the world (375 million eligible voters in 2009).

It has been directly elected every five years by universal suffrage since 1979. However, turnout at European Parliament elections has fallen consecutively at each election since that date, and has been under 50% since 1999. Turnout in 2014 stood at 42.54% of all European voters.

Although the European Parliament has legislative power that the Council and Commission do not possess, it does not formally possess legislative initiative, as most national parliaments of European Union member states do. The Parliament is the "first institution" of the EU (mentioned first in the treaties, having ceremonial precedence over all authority at European level), and shares equal legislative and budgetary powers with the Council (except in a few areas where the special legislative procedures apply). It likewise has equal control over the EU budget. Finally, the European Commission, the executive body of the EU, is accountable to Parliament. In particular, Parliament elects the President of the Commission, and approves (or rejects) the appointment of the Commission as a whole. It can subsequently force the Commission as a body to resign by adopting a motion of censure.

Merseyside (/ˈmɜːrzisaɪd/) is a metropolitan county in North West England, with a population of 1.38 million. It encompasses the metropolitan area centred on both banks of the lower reaches of the Mersey Estuary, and comprises five metropolitan boroughs: Knowsley, St Helens, Sefton, Wirral, and the city of Liverpool. Merseyside, which was created on 1 April 1974 as a result of the Local Government Act 1972, takes its name from the River Mersey.

Merseyside spans 249 square miles (645 km²) of land which border Lancashire (to the north-east), Greater Manchester (to the east), Cheshire (to the south and south-west) and the Irish Sea to the west. North Wales is across the Dee Estuary. There is a mix of high density urban areas, suburbs, semi-rural and rural locations in Merseyside, but overwhelmingly the land use is urban. It has a focused central business district, formed by Liverpool City Centre, but Merseyside is also a polycentric county with five metropolitan districts, each of which has at least one major town centre and outlying suburbs. The Liverpool Urban Area is the fifth most populous conurbation in England, and dominates the geographic centre of the county, while the smaller Birkenhead Urban Area dominates the Wirral Peninsula in the south.

Merseyside (West) is a regional English Rugby Union league for teams from the Merseyside area. The top two clubs are promoted to South Lancs/Cheshire 1 or to North Lancashire/Cumbria.

Participating Clubs 2015-16

See also