Commerce and industry have characterized the Buchanan Downtown Historic District since mill owner Charles Cowles settled here in the 1830s. McCoy's Creek supplied millraces and more than fifteen mills. The circa 18440 Day and Hamilton race supported William Bainton's 1857-58 flour mill, which became Pears Mill. In 1863 John D. Ross and Lorenzo Alexander built the Union Block with its third floor event hall. The district was listed on the National Register of Historic Places in 2009.
After a disastrous 1862 fire, merchants built more than twenty brick Italianate buildings in this historic district, In 1904, the Buchanan Improvement Association persuaded Chicago's George R. Rich Manufacturing Company to relocate here. Renamed Clark Equipment in 1916, it built employee housing during World War I and adjusted its payroll practices to stabilize the local economy in the 1930s. It was a major Buchanan employer for decades and a Fortune 500 Coompany.