Reva, South Dakota Reva, South Dakota Reva is an unincorporated community in Harding County, South Dakota, United States. Although not tracked by the Census Bureau, Reva has been assigned the ZIP code of 57651. The community has the name of Reva Bonniwell, the daughter of a first settler. The Battle of Slim Buttes occurred here on September 9–10, 1876, in the Great Sioux Reservation between the United States Army and Miniconjou Sioux during the Great Sioux War of 1876. It marked the first significant victory for the Army since the stunning defeat of General George Custer at the Battle of Little Bighorn in
Little Bighorn River The Lakota Sioux, who began to contest control of this area with the Crow in the 1840s to 1860s as they pushed westward, continued to call the river the "Greasy Grass". Native Americans called the river the Greasy Grass before the Battle of the Little Big Horn in 1876, and Lakota people still commonly refer to the Battle of the Little Bighorn as the Battle of the Greasy Grass. In historical references in Wikipedia articles, the Battle of the Little Bighorn is also referred to as the Battle of the Greasy Grass, as it is in the discussions of the