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
Battle of the Little Bighorn the three Crow scouts, but also accompanied by General Charles Woodruff "as I particularly desired that the testimony of these men might be considered by an experienced army officer". Finally, Curtis visited the country of the Arikara and interviewed the scouts of that tribe who had been with Custer's command. Based on all the information he gathered, Curtis concluded that Custer had indeed ridden down the Medicine Tail Coulee and then towards the river where he probably planned to ford it. However, "the Indians had now discovered him and were gathered closely on the opposite side". They were soon joined