He was the fourth son of Charles-Armand de Gontaut, duc Biron, and Marie Antoinette, Duchess of Lauzun. He joined the army as an adolescent. He fought in Italy (attack on the Milan castle, Tortona and the Battle of San Pietro).
He was the fourth son of Charles-Armand de Gontaut, duc Biron, and Marie Antoinette, Duchess of Lauzun. He enlisted in the military as a teenager. He participated in Italy (siege of the Milan fortress, Tortona, and the Battle of San Pietro).