Answer: Mostly all of them their isn't a number per say because they didn't keep record.
This way, in 1874, many Sioux followed the order, given by the federal government, of remaining on the reservation in which they were already living. However, the federal government violated the terms of the Laramie Treaty in 1874, when it sent American troops led by George A. Custer within the limits of the Native American Sioux reserve, headed for the Black Hills in search of gold.