In 1784 he became a major general, in 1787 governor-general of the Crimea; and under Suvorov, whose disciple he became, he won considerable distinction in the Russo-Turkish War (1787–1792), at the taking of Ochakov, Odessa, Bender, and Izmail, and in the battles of Rymnik (1789) and Mashin (July 1791). He became a lieutenant-general (March 1791) and successively occupied the positions of ambassador at Istanbul, commander of Russian forces in Finland, commandant of the corps of cadets at Saint Petersburg, ambassador at Berlin, and governor-general of Saint Petersburg (1801–1802).