Although initially in the Army of France during the Seven Years' War, Wurmser left France after Louis reached a peace agreement with Britain, and joined the military of the House of Habsburg. He later took part in the short-lived War of the Bavarian Succession, also called the so-called "Kartoffelkrieg" (Potato War). During the French Revolutionary Wars, Wurmser commanded several imperial Habsburg armies on in the Rhine River valley between 1793 and 1795, and perhaps his most conspicuous achievement was the taking of the lines of Lauterburg and Weissenburg in October 1793.