Edwardsville is a city located in, and is the county seat of, Madison County, Illinois, United States. As of the 2020 census, the population was 26,808. The city was named in honor of Ninian Edwards, then Governor of the Illinois Territory. Edwardsville is a part of Southern Illinois and the Metro East region within Greater St. Louis, located 18 miles (29 km) northeast of downtown St. Louis.

Madison County is a county in the U.S. state of Illinois. It is a part of the Metro East in southern Illinois. According to the 2020 census, it had a population of 264,776, making it the eighth-most populous county in Illinois and the most populous in the southern portion of the state. The county seat is Edwardsville, and the largest city is Granite City.