The Fort de La Présentation, a mission fort, was built in 1749 and so named by the French Sulpician priest, Abbé Picquet. It was also sometimes known as Fort La Galette. It was built at the confluence of the Oswegatchie River and the St Lawrence River in present day New York. The French wanted to strengthen their alliance with the powerful Iroquois, as well as convert them to Catholicism. With increasing tensions with Great Britain, they were concerned about their thinly populated Canadian colony. By 1755 the settlement included 3,000 Iroquois residents loyal to France, in part because of the fur trade, as well as their hostility to encroachment by British colonists in their other territories. By comparison, Montréal had only 4,000 residents. In 1758, with the Seven Years' War intensifying, a French-Canadian military commander took charge of a garrison at the fort. In 1759, French military forces abandoned the fort to move to Fort Lévis. Ultimately the British besieged that fort and Montreal.After the British victories of 1760, the French ceded their Canadian territory to Great Britain. The British renamed it Fort Oswegatchie. It remained under their control until 1796, after Jay's Treaty, when redefinition of the northern boundary caused the land to be taken over by the United States. The first settlement under an American flag began that year. American residents named the town Ogdensburg after early settler Samuel Ogden.
