Macomb is a city in and the county seat of McDonough County, Illinois, United States. It is situated in western Illinois southwest of Galesburg. The population was 22,086 at the 2010 census. Macomb is the home of Western Illinois University
First settled in 1829 on a site tentatively named Washington, the town was officially founded in 1830 as the county seat of McDonough County and given the name Macomb after General Alexander Macomb, a general in the War of 1812. War veterans were given land grants in the Macomb area, which was part of the "Military Tract" set aside by Congress. In 1855 the Northern Cross Railroad, a predecessor to theChicago, Burlington and Quincy Railroad, was constructed through Macomb, leading to a rise in the town's population. In 1899 the Western Illinois State Normal School, later Western Illinois University, was founded in Macomb. Representative Lawrence Sherman was instrumental in locating the school in Macomb. In 1903 the Macomb and Western Illinois Railway was built from Macomb to nearby Industryand Littleton by local financier Charles V. Chandler, though this railroad was abandoned in 1930. In 1918, construction on Illinois Route 3 was begun as a state financed highway from Cairo to Rock Islandthrough Macomb; in the late 1920s U.S. Route 67 was extended along this route to Dubuque, Iowa.