In 1799 Loudon led a grenadier brigade at Novi and in a few other actions. Promoted again, he was transferred to Poland in 1800 and missed Marengo. In the War of the Third Coalition he fought at Elchingen and was captured by the French at Ulm. He commanded second-line troops in the 1809 campaign and retired from military life soon after. He died at Hadersdorf in 1822.