He accompanied Louis XV in the campaign of 1744-48 and attained high military rank, which owed more to his courtiership than to his generalship. Soon after the beginning of the Seven Years' War, through the influence of Mme de Pompadour, he was put in command of a corps of 24,000 men, and in November 1757 he sustained the crushing defeat of Rossbach.
He was more fortunate, however, in his later military career, and continued in the service until the general peace of 1763, after which he lived the life of an ordinary courtier and man of fashion in Paris.
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