Oswego ( oss-WEE-goh) is a city in and the county seat of Oswego County, New York, United States. The population was 16,921 at the 2020 census. Oswego is situated at the mouth of the Oswego River on the southeastern shore of Lake Ontario in Upstate New York, about 40 miles (64 km) northwest of Syracuse and 74 miles (119 km) east-northeast of Rochester by road. The city promotes itself as "The Port City of Central New York".
The first European settlement at Oswego was a British trading post established in 1722, and it was first incorporated as a village in 1828 before becoming a city in 1848. British forces briefly captured the city during the War of 1812, but were defeated nearby later that same month. The canalization of the Oswego River was a major boon to Oswego, attracting settlement and investment; this was later bolstered by its status as a rail hub for much of the 19th and 20th centuries, though this status had begun to decline by the 1940s. During World War II, Fort Ontario was the site of the only Jewish refugee camp in the United States. Today, the city's economy is primarily based around manufacturing and services.