where in illinois is cahokia
For the extinct Native American tribe unrelated to the builders of the Cahokia Mounds, see Cahokia (tribe). Cahokia is a village in St. Clair County, Illinois, United States. It is part of Greater St. Louis metropolitan area. As of the 2010 census, the village had a population of 15,241, a decline from 16,391 in 2000.