Some of the cities, towns, and places in Buchanan County are Agency, Bloomington, Center, Crawford, De Kalb, Easton, Faucett, Halls, Jackson, Lake, Lewis and Clark Village, Marion, Platte, Rush, Rushville, St. Joseph, Tremont, Wallace, Washington, Wayne
Buchanan County is located in the U.S. state of Missouri. As of the 2010 United States Census, the population was 89,201. Its county seat is St. Joseph. When originally formed in 1838, the county was named Roberts County, after settler Hiram Roberts. It was renamed in 1839 for James Buchanan, then a U.S. Senator and later President of the United States. The county was formed from land annexed to Missouri, as were five other counties.
Buchanan County is included in the Kansas City CSA.