Charles XIV and III John, also known as Carl John, (Swedish and Norwegian: Karl Johan; 26 January 1763 – 8 March 1844) was King of Sweden (as Charles XIV John) and King of Norway (as Charles III John) from 1818 until his death, and served as de facto regent and head of state from 1810 to 1818. He was also the Sovereign Prince of Pontecorvo, in south-central Italy, from 1806 until 1810.

He was born Jean Bernadotte in France and served a long career in the French Army. He subsequently acquired the full name of Jean-Baptiste Jules Bernadotte (French: [ʒɑ̃ bapˈtist ʒyl bɛʁˈnadɔt]). He was appointed as a Marshal of France by Napoleon, though the two had a turbulent relationship. Napoleon made him Prince of Pontecorvo on 5 June 1806, but he stopped using that title in 1810 when his service to France ended and he was elected the heir-presumptive to the childless King Charles XIII of Sweden. His candidacy was advocated by Baron Carl Otto Mörner, a Swedish courtier and obscure member of the Riksdag of the Estates. Upon his Swedish adoption, he assumed the name Carl. He did not use the name Bernadotte in Sweden, but founded the royal dynasty there of that name.

Bernadotte was born in Pau, France, as the son of Jean Henri Bernadotte (Pau, Béarn, 14 October 1711 – Pau, 31 March 1780), prosecutor at Pau, and his wife (married at Boeil, 20 February 1754) Jeanne de Saint-Jean (Pau, 1 April 1728 – Pau, 8 January 1809), niece of the Lay Abbot of Sireix. The family name was originally du Poey (or de Pouey), but was changed to Bernadotte – a surname of an ancestress at the beginning of the 17th century. Soon after his birth, Baptiste was added to his name, to distinguish him from his elder brother Jean Évangeliste. Bernadotte himself added Jules to his first names as a tribute to the French Empire under Napoleon I.

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