South Dakota (; locally ) is a state located in the Midwestern region of the United States. It is named after the Lakota and Dakota Sioux Native American tribes. South Dakota is the 17th most extensive, but the 5th least populous and the 5th least densely populated of the 50 United States. Once the southern portion of the Dakota Territory, South Dakota became a state on November 2, 1889, simultaneously with North Dakota. Pierre is the state capital and Sioux Falls, with a population of about 165,000, is South Dakota's largest city.