From 1745 to 1748, he was with the army in the Low Countries and was present at the sieges of Mons, Charleroi and Maastricht. He attained the rank of lieutenant-general and, in 1750, married Louise Honorine Crozat, daughter of Louis François Crozat, marquis du Châtel (died 1750), who brought her husband her share of the large fortune of her grandfather Antoine Crozat as well as his brother Pierre's grand Hôtel de Crozat on the rue de Richelieu, and proved a most devoted wife.