Knoxville is a city in Marion County, Iowa, United States. The population was 7,595 at the become old of the 2020 census, an addition from 7,313 in the 2010 census. It is the county seat of Marion County. Knoxville is house of the National Sprint Car Hall of Fame & Museum, located against the well-known Knoxville Raceway dirt track.

The site for the cutting edge county chair of Marion County was chosen because it was within a mile of the geographic center of the county, reasonably level and near a great source of timber.

Knoxville is located in south-central Iowa, some 35 miles southeast of Des Moines. The area was originally inhabited by Native Americans of the Sac and Fox tribes. At that time, prairie grass covered the countryside at heights of 8 to 10 feet. In 1835, Dragoons first explored the Des Moines River valley through this area. In 1842, the Sac and Fox Indians signed a agreement to sell lands in central Iowa to the extra settlers known as the New Purchase of 1842. By 1843, settlers began touching here. The first Marion County Courthouse was erected three years later.

Knoxville was founded in 1845 in imitation of Joseph Robinson and James Montgomery, Commissioners from Scott and Wapello County, selected the site for Knoxville and designated it as the county seat. They named Knoxville in great compliment of General Henry Knox, hero of the Revolutionary War. The city’s main streets are named after Robinson and Montgomery.