 Complete the following phrase:  Born in an aristocratic family of the Ancien Régime, Desvaux was admitted at the Artillery School of Châlons in 1792, before joining the Army of the Alps, with which he would take part to the siege of Lyon. He then served under the command of general Jacques François Dugommier in the Army of the Oriental-Pyrenees, before being named aide-de-camp to general Saint-Rémy in January 1796 and sent to Italy. He would take part to several military engagements between 17981799, most noteworthy at Novi and Mincio. He becomes aide-de-camp to general Auguste de Marmont and is promoted to the rank of colonel in 1803, taking part to the 