Britain defeated France in the Seven Years' War, the French transferred the fort to British forces, who occupied it in October 1761. Pontiac's War On May 25, 1763, during Pontiac's War, the fort, manned by 14 soldiers from the 60th Regiment of Foot, was captured by Potawatomi warriors. They killed most of the garrison outright, and took the commander, Ensign Francis Schlosser, captive along with three other soldiers. The Potawatomi took them to Fort Detroit to be ransomed as prisoners of war, as was common practice for high-ranking military personnel. After the conflict, the British maintained the fort as a trading post, but did not garrison it again until 1779, during the American Revolutionary War. American Revolutionary War Raid of 1780 During the American Revolutionary War, pro-British traders used Fort St. Joseph to equip the Miami, Potawatomi, and other British-allied Native Americans. In 1780, a Patriot force from Cahokia, Illinois, led by Jean-Baptiste Hamelin and Lieutenant Thomas Brady, raided the fort, plundering its content and capturing several traders. Detroit Militia officer Antoine Dagneaux de Quindre, an officer in British service, led forces after the raiding party; he overtook and defeated them near the Petit Fort. Spanish Expedition of 1781 After the defeat of Hamelin's party, two Milwaukee chiefs, El Heturnò and Naquiguen, traveled to Spanish-held St. Louis; they arrived on 26 December 1780, to report the failed raid. They asked for assistance to raid the fort again. Don Francisco Cruzat, Commandant of St. Louis, dispatched the militia Captain Don Eugenio Pouré with 60 volunteers and Native allies. The force also included Ensign Charles Tayon and the interpreter Louis Chevalier. The Spanish and Native force travelled via the Illinois River and Kankakee River to modern Dunns Bridge, Indiana. There they turned northeast and marched overland to Fort St. Joseph. Before the Spanish and their allies attacked the fort, they promised the Potawatomi half the bounty if they would remain neutral. Captain Pouré took Fort St. Joseph by surprise on 12 February 1781 by racing across the frozen river and taking the fort before the defenders, who consisted solely of a Canadien trader named Duquier and several of his employees, could go to arms. He had the Spanish colors raised and claimed Fort St. Joseph and the St. Joseph River for Spain. His troops plundered the fort for one day, distributing the goods among natives before departing. Lt. Dagneau de Quindre arrived