Yankton, city, seat of Yankton County, southeastern South Dakota, on the Missouri River, near its confluence with the James River, in a grain- and livestock-producing area; incorporated as a city 1869. Products of the city include mining and construction equipment, electronic equipment, precision machine parts, and greenhouse plants. Mount Marty College (1936) is here, and Lewis and Clark Lake, located nearby, is the focus of a popular recreation area. The community, settled in 1858, is named for the Yankton people. It was the capital of the Dakota Territory from 1861 to 1883. Population 12,011 (1980); 12,703 (1990); 13,528 (2000).
