Kewanee is a city in Henry County, Illinois. "Kewanee" is the Winnebago word for greater prairie chicken, which lived there. The population was 12,509 in the 2020 census, down from 12,944 in 2000.

Henry County is a county located in the U.S. state of Illinois. The 2020 United States Census, listed its population at 49,284. Its county seat is Cambridge.