Military engineering
A memoir on the Greek island of Corfu addressed to Napoleon Bonaparte earned him his appointment as supernumerary in Military engineering. He was Lieutenant during the Polish campaign, Captain during the Spanish Civil War (1808), he took part in the sieges of Saragossa (1808–1809) and Figueres (1811). He was created a Knight of the Empire on 23 February 1811, he became aide-de-camp to General Clarke. After a mission to the Ionian islands, he was besieged in Danzig in 1813 with General Rapp. He was appointed Colonel in 1815. Prisoner of War, he returned to France in 1814 and was, during the Hundred Days, Chief of Staff of Rapp, who commanded the 5th Corps, assigned to cover the Rhine.