Hamilton, city, seat of Butler County, southwestern Ohio, on the Great Miami River, near Cincinnati; settled late 1780s, incorporated as a city 1857. It is a commercial and industrial hub; manufactures include paper, security devices, construction materials, motor-vehicle parts, iron and steel, and metal products. A junior college (1965), affiliated with nearby Miami University, is here. The community grew around Fort Hamilton, built here in 1791 and named for Alexander Hamilton. Its growth was spurred by the opening of the Miami-Erie Canal in 1827. By the 1840s it was an industrial center with foundries and casting firms, many of which had been started by German immigrants. Population 63,189 (1980); 60,690 (2000).
