Greenville is a city in Washington County, Mississippi, United States. The population was 41,633 at the 2000 census, but according to the 2007 census bureau estimates, it has since declined to 35,764, making it the eighth largest city in the state. It is the county seat of Washington County. Greenville was named after American Revolutionary War hero Nathanael Greene. Greenville is located on the eastern bank of Lake Ferguson, an oxbow lake left from an old channel of the Mississippi River. Two floating casinos are located on the lake near the downtown area, with a third just west of the city near the Greenville Bridge. Chicago Mill and Lumber Co. operated a lumber mill on the lake .2 mile south of the casino levee parking lot; the mill specialized in making hardwood boxes until it closed. The Winterville Mounds Historic Site, with museum and picnic area, is located just north of the town at 2415 Highway 1 N; the Indian mounds were built by a tribe that predated the Choctaw and Chickasaw Indian tribes.