The territory that would become South Dakota was added to the United States in 1803 as part of the Louisiana Purchase.The first permanent American settlement was established at Fort Pierre by the Lewis and Clark expedition in 1804.White settlement of the territory in the 1800sled to clashes with the Sioux, as some of the land had been granted to the tribe by an earlier treaty. Nevertheless, the territory was incorporated into the union on November 2, 1889, along with North Dakota. Due to a controversy over which state would be admitted to the union first, President Benjamin Harrison shuffled the bills and signed one at random, with the order going unrecorded, though North Dakota is traditionally listed first. Today, a major part of South Dakota’s economy is fueled by tourism–visitors flock to the state to see Mt. Rushmore, which features 60-foot-tall sculptures of the faces of Presidents Washington, Jefferson, Roosevelt and Lincoln. Famous South Dakotans include newscaster Tom Brokaw, senator and vice president Hubert Humphrey and model-actress Cheryl Ladd.