Erie County is a county located in the U.S. state of New York. As of the 2010 census, the population was 919,040. The county seat is Buffalo. The county's name comes from Lake Erie, which in turn comes from the Erie tribe of American Indians who lived south and east of the lake before 1654. Erie County is part of the Buffalo–Niagara Falls Metropolitan Statistical Area. The southern part of the county is known as the Southtowns.