1733 also saw Europe's peace broken for the first time in twenty years after the death of Augustus, king of Poland.

Inheriting his father's dukedom and becoming a peer of France, Charles continued serving with the French army on the Rhine under the orders of Marshal de Coigny from 1735 until the peace of Vienna in 1738.

Charles VI's death in 1740 triggered another European war, with France backing the elector of Bavaria's claims to the imperial throne.

In 1741, a French army of 40,000 men crossed the Rhine at Fort-Louis, under the orders of the Charles Louis Auguste Fouquet, whilst another army the same size crossed the Meuse at the same time - Charles served in the latter as a brigadier, under the orders of Jean-Baptiste Francois des Marets, marquis de Maillebois.

Returning to France in July 1743, he ended his campaign in Basse-Alsace serving under Marshal de Noailles.

In the lost Battle of Minden, fought on 1 August 1759, he was in command of the entire French cavalry, with which he charged the enemy without success.