Galesburg is a city in Knox County, Illinois, United States. The city is 45 miles (72 km) northwest of Peoria. At the 2010 census, its population was 32,195. It is the county seat of Knox County and the principal city of the Galesburg Micropolitan Statistical Area, which includes all of Knox and Warren counties.

Knox County is a county in the U.S. state of Illinois. According to the 2020 census, it had a population of 49,967. Its county seat is Galesburg.