In 1866, Sitting Bull was made the principal chief of the northern Sioux Indian tribe. Crazy Horse was named vice-chief. In 1867, Sitting Bull was named chief of the entire Sioux nation. Together, Sitting Bull and Crazy Horse waged a campaign against the U.S. military as it expanded into the West. After a dispute about the location of the Sioux reservation (the Sioux were forced to move from their original spot because gold was found in the Black Hills of South Dakota), General George Crook fought with Sitting Bull and representatives of the Cheyenne and Arahapo tribes. In the Battle of the Rosebud, on 17 June, Crook's men were forced to retreat in the face of defeat. Sitting Bull subsequently moved his encampment into the Valley of …
Richert, Lucas Paul. "Sioux Chief Sitting Bull gives himself up to the US army ". The Literary Encyclopedia. First published 20 January 2009; last revised 30 November -1.
[http://www.litencyc.com/php/stopics.php?rec=true&UID=5261, accessed 19 April 2015.]