Still leading the 26th Chasseurs, Digeon took part in the Ulm Campaign in 1805, including Lensberg, and Battle of Austerlitz, where he took three standards. He received the decoration of Commander of the Legion of Honor after the battle, where he was wounded. He was near Stralsund in 1807. Elevated to the rank of general of brigade, he served in General Marie Victor de Fay, marquis de Latour-Maubourg's 1st Dragoon Division as the brigadier in command of the 20th and 25th Dragoons. The same year he commanded with great distinction in the Battle of Heilsberg and in the Battle of Friedland.