[2] He left Bavaria on the death of Charles VII, and after brief service under Frederick the Great joined Marshal Saxe in the Netherlands and was created a field-marshal of the French army.

On the outbreak of the Seven Years' War (1756) he was appointed lieutenant-general, and although he showed greater ability than any of his fellow-commanders and was admired by his soldiers, he fell a victim to court intrigues, professional jealousy and hostile criticism.

[3] In 1767, he and his circle, wished to make Birgitte Sofie Gabel the official mistress of Christian VII of Denmark-Norway in order to divert him from politics and take over the de facto power over the government themselves.

He soon returned to France, bought a small estate in Alsace near Lauterbach (close to Mulhouse),[5] and devoted his time to religion and farming.

A financial crisis swept away the funds that he had saved from his Danish service and rendered him dependent on the bounty of the French ministry of war.