The Illinois State Fair is an annual festival, centering on the theme of agriculture, hosted by the U.S. state of Illinois in the state capital, Springfield. The state fair has been celebrated almost every year since 1853. Currently, the fair is held annually at the Illinois State Fairgrounds over an 11-day period in mid-August of each year.

Springfield is the capital city of the U.S. state of Illinois and the county seat of Sangamon County. The city's population was 114,394 at the 2020 census, which makes it the state's seventh most-populous city, the second largest outside of the Chicago metropolitan area, and the largest in central Illinois. Approximately 208,000 residents live in the Springfield metropolitan area.