Fort Oswegatchie, originally Fort de la Présentation, was built in 1749 by French missionary Abbé François Picquet as a mission to the Iroquois and a supply base for French expeditions into the interior of the American continent. Britain took control of the fort in 1760 after defeating the French at the Battle of the Thousand Islands and renamed it Fort Oswegatchie when occupying the abandoned French mission at the end of the French & Indian War. The fort became a strategic British foothold in the St. Lawrence Valley and, though on American territory after the American Revolution, remained under British control, aiding the settlement and supply of refugee British Loyalists along the north shore of the St. Lawrence River and Lake Ontario. In September 1775, Captain George Forster led soldiers of the 8th Regiment of Foot, together with militia and Iroquois allies, from the fort to Les Cedres, 28 miles west of Montreal, where they defeated Continental troops defending a small stockade; after pushing onto the Island of Montreal, Forster's forces used two four-pounder guns captured at Les Cedres to prevent Brigadier General Benedict Arnold's soldiers from pursuing them across the Ottawa River. During General Burgoyne's campaign to divide the colonies by controlling the Hudson River, Colonel Barry St. Leger's forces likely stopped at Fort Oswegatchie on their way to besiege Fort Stanwix at the head of the Mohawk River, but the siege failed and the force could not continue to join Burgoyne at Albany. British forces at Oswegatchie and their Indian allies continued to support raids into the Mohawk Valley, attacking Fort Stanwix and raiding Fort Dayton, Canada Creek, and Ellice's Mill at Little Falls, taking food, forage, and livestock. The fort also supported shipbuilding: two armed vessels called snows, the 16-gun Haldimand and the 18-gun Seneca, were built there above the St. Lawrence rapids so they could sail into Lake Ontario and reach the Oswego and Niagara Rivers and other strategic points. Nearly 20 years after the American Revolution, the Jay Treaty forced Britain to evacuate forts in American territory, and in 1796 Americans took control of the fort; Nathan Ford, an agent of land speculator Samuel Ogden, arrived with the first American settlers and established his office there, the fort was renamed Fort Presentation in recognition of its original French name, and the new community was named after Samuel Ogden.