The corps was reformed in 1812 for the invasion of Russia. Commanded by General Louis-Pierre Montbrun, the initial strength of the corps was 10,436 cavalry and 30 horse artillery pieces. General Horace François Bastien Sébastiani de La Porta led the 2nd Light Cavalry Division, General Pierre Watier directed the 2nd Heavy Cavalry Division, and General Jean-Marie Defrance commanded the 4th Heavy Cavalry Division.