Jean Baptiste Joseph, chevalier de Laumoy (1750–1832) French engineer, fought in the American Revolutionary War, and was on the staff of Lafayette and was captured with him, by the Austrians. De Laumoy was the son of a French infantry captain. He entered the French military engineering school in 1760. He was assigned to America in 1777. On 17 November Laumoy was commissioned Colonel of Engineers; he joined Washington's winter camp at Valley Forge. The French engineers, de Laumoy, La Radiere, and Duportail, provided knowledge of European fortifications and siege warfare.