Fort Ontario Fort Ontario is a historic fort situated by the City of Oswego , in Oswego County , New York in the United States of America . It is owned by the state of New York and operated as a museum known as Fort Ontario State Historic Site . Geography and early history . Fort Ontario is located on the east side of the Oswego River on high ground overlooking Lake Ontario . Fort Ontario was one of several forts erected by the British to protect the area around the east end of Lake Ontario . The original Fort Ontario was erected in 1755 , during the French and Indian War in order to bolster defenses already in place at Fort Oswego on the opposite side of the river . At that time its name was the " Fort of the Six Nations , " but the fort was destroyed by French forces and rebuilt by British forces in 1759 . At the conclusion of Pontiac ' s War , Chief Pontiac urged moderation and agreed to travel to New York , where he made a formal treaty with William Johnson at Fort Ontario on July 25 , 1766 . During the American Revolutionary War , a detachment from the 3rd New York Regiment destroyed the fort in July , 1778 , after the British abandoned it . The British returned and rebuilt the fort in 1782 . There was an aborted attack on the fort by Colonel Marinus Willet in 1783 . The British held the fort after the war was over until 1796 after the signing of Jay ' s Treaty . Nineteenth century . The fort was attacked and destroyed by British forces during the War of 1812 in the year 1814 . After a period of disuse , new construction was undertaken in part due to tensions with Great Britain as well as to check smuggling activities between Canada and the United States . During the American Civil War the new construction began at the fort due to fear of British help from Canada to the South . Although the fort remained a military base , the fort itself fell into ruin , since funds were used to create more modern quarters outside the fort . The modern fort . The 2nd Brigade of the U . S . 1st Infantry Division called Fort Ontario home until the brigade was inactivated on June 1 , 1940 . During World War II , Fort Ontario was home to approximately 982 Jewish refugees , from August 1944 to February 1946 . The Fort Ontario Emergency Refugee Shelter was the only attempt by the United States to shelter Jewish refugees during the war . After the end of the war the refugees were kept in internment due to disagreements concerning whether or not to allow them to become United States citizens . In January 1946 , the decision was made to allow them to become citizens , and by February all of the Jewish refugees were allowed to leave Fort Ontario . The restored fort is open to the public as a state historic site . It was listed on the National Register of Historic Places in 1970 . In 2010 , Fort Ontario was one of the state - funded historical sites named by Governor David Paterson as being potentially unfunded due to the budget crisis faced by New York State . In response , many of the citizens of Oswego and students of the State University of New York at Oswego have joined together in support of the historical site . Fort Ontario was built with two other forts in the period , Fort George and Fort Oswego .