Career
He is chiefly remembered for his role in advocating for Frenchman Jean Baptiste Bernadotte"s succession to the Swedish crown in 1810. In 1810 King Charles XIII of Sweden was childless and the crown prince Charles August had died of a stroke. Baron Mörner, entirely on his own initiative, offered the succession to the Swedish crown to Bernadotte.
Although the Swedish government, amazed at Mörner"s effrontery, placed him under arrest, the candidature of Bernadotte gradually gained favor and on 21 August 1810 in Örebro he was elected by the Riksdag of the Estates to be the new Crown Prince, and was subsequently made Generalissimus of the Swedish Armed Forces by the King.
He was crowned Charles XIV of Sweden on 5 February 1818.