She was politically active and acted as adviser of her second spouse, nobleman Carl Carlsson Mörner (1755–1821).
Her brother, merchant Carl Abraham Arfwedson (1774-1861), was a personal friend of the Swedish queen, Désirée Clary.
Charlotta Arfwedson first married Colonel Lieutenant Baron Casper Wrede, whom she later divorced.
In 1810, she married politician Count Carl Mörner, who served as Governor-general of Norway.
He followed her advice, she wrote and edited his speeches and handled his correspondence with the French-born heir to the throne, Charles XIV John of Sweden, who could not speak Swedish.