In 1799, Bellegarde commanded a corps in eastern Switzerland, connecting the armies of Archduke Charles and Aleksandr Suvorov, and finally joined the latter in north Italy. He conducted the siege of the citadel of Alessandria, and was present at the decisive Battle of Novi. After the Austrian defeat at the Battle of Marengo (in which his brother Friedrich Bellegarde commanded a brigade), Emperor Francis II of Austria appointed Bellegarde to command the army in Italy with the rank of General of Cavalry. On 25 December, the French defeated Bellegarde at the Battle of Pozzolo.