In the course of the American Revolution, Manning was serving as president of Brown in 1780 when French troops under the command of the Comte de Rochambeau, who led troops sent by King Louis XVI of France, landed in Newport, Rhode Island to aid American troops under the command of General George Washington in the American Revolutionary War. These allied troops were based in Rhode Island for a year before they embarked on a 600-mile (970 km) march in 1781 from Rhode Island to Virginia, where they fought and defeated British forces sent by King George III of the United Kingdom on the Yorktown, Virginia peninsula in the Siege of Yorktown and the Battle of the Chesapeake. During the year of preparation in Rhode Island, the Brown campus was turned into an encampment site for soldiers, and the College Edifice at Brown (later renamed University Hall) was converted into a military hospital.