On 2 July 1733 at the age of eight, he was made a "maréchal de camp" (field marshal) and the next year, a "lieutenant général" (lieutenant general). In 1740, he received the "Ordre de la Toison d'or" from his Bourbon cousin, the King of Spain. In 1742, King Louis XV conferred upon him the "Order of the Holy Spirit". He served in the military under his maternal uncle, the maréchal-duc de Noailles, and fought brilliantly at Dettingen in 1743 and Fontenoy in 1745.