Jean-Baptiste Donatien de Vimeur was born in Vendôme, in the province of Orléanais, and he was schooled at the Jesuit college in Blois. After the death of his elder brother, he entered a cavalry regiment and served in Bohemia, Bavaria, and on the Rhine during the War of the Austrian Succession. By 1747, he had attained the rank of colonel. He took part in the Siege of Maastricht (1748) and became governor of Vendôme in 1749. He distinguished himself in the Battle of Minorca (1756) on the outbreak of the Seven Years' War and was promoted to Brigadier General of infantry. In 1758, he fought in Germany, notably in the Battle of Krefeld and the Battle of Clostercamp, receiving several wounds at Clostercamp.