Shawnee County (county code SN) is a county located in northeast Kansas, in the central United States of America. As of the 2010 census, the population was 177,934 making it the third-most populous county in Kansas. Its most populous city, Topeka, is the state capital and county seat. The county was one of the original 33 counties created by the first territorial legislature in 1855, and it was named for the Shawnee tribe of Native Americans.