Erie County is a county 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 Native Americans who lived south and east of the lake before 1654. Erie County is part of the Buffalo–Niagara Falls metropolitan area. The county's southern part is known as the Southtowns.