Charles III may refer to:

Charles III (Spanish: Carlos; Italian: Carlo; 20 January 1716 – 14 December 1788) was the King of Spain and the Spanish Indies from 1759 to 1788. He was the fifth son of Philip V of Spain, but eldest by his second wife, Elisabeth Farnese. In 1731, the 15-year-old Charles became the Duke of Parma and Piacenza, as Charles I, on the death of his childless granduncle Antonio Farnese.

In 1734, as Duke of Parma, he conquered the kingdoms of Naples and of Sicily, and was crowned king on 3 July 1735, reigning as Charles VII of Naples and Charles V of Sicily. In 1738 he married Princess Maria Amalia of Saxony, an educated, cultured woman who gave birth to 13 children, eight of whom reached adulthood. Charles and Maria Amalia resided in Naples for 19 years; she died in 1760.

Upon succeeding to the Spanish throne on 10 August 1759, Charles, a proponent of enlightened absolutism, on 6 October 1759 abdicated the Neapolitan and Sicilian thrones in favour of Ferdinand, his third surviving son, who became Ferdinand I of the Two Sicilies.

Charles III (17 September 879 – 7 October 929), called the Simple or the Straightforward (from the Latin Carolus Simplex), was the King of Western Francia from 898 until 922 and the King of Lotharingia from 911 until 919–23. He was a member of the Carolingian dynasty.

Early life

Charles was the third and posthumous son of Louis the Stammerer by his second wife, Adelaide of Paris. As a child, Charles was prevented from succeeding to the throne at the time of the death in 884 of his half-brother Carloman. The nobles of the realm instead asked his cousin, Charles the Fat, to rule them. He was also prevented from succeeding the unpopular Charles, who was deposed in November 887 and died in January 888, although it is unknown if his deposition was accepted or even made known in West Francia before his death. The nobility elected as king Odo, the hero of the Siege of Paris, though there was a faction that supported Guy III of Spoleto. Charles was put under the protection of Ranulf II, the Duke of Aquitaine, who may have tried to claim the throne for him and in the end used the royal title himself until making peace with Odo.