"Pine Ridge, November 1890 - January 1891.
Accumulated grievances, aggravated by teachings of an Indian prophet named Wovoka, who claimed to be the Messiah, brought about this last major conflict with the Sioux. General Miles, commander of the Department of the Missouri, responded to a Department of Interior request to check the rising ferment by ordering apprehension of the great Sioux leader, Sitting Bull, who was killed during the attempted arrest at Standing Rock Agency on 15 December 1890. Meanwhile, large numbers of Sioux had been assembling in the Bad Lands, and a serious clash took place at Wounded Knee Creek on 29 December 1890 between Col. James W. Forsyth's 7th Cavalry and Chief Big Foot's Band with considerable losses on both sides. Almost half the infantry and cavalry of the Regular Army (including elements of the 1st, 6th, 7th, 8th, and 9th Cavalry and the 1st, 2nd, 3rd, 7th, 8th, 12th, 16th, 17th, 20th, 21st, 22nd, and 25th Infantry, as well as the 4th Artillery) were concentrated in the area, and in January 1891 the warriors were disarmed and persuaded to return peaceably to their reservations."
The description of the "clash" doesn't seem to match the facts, I can understand why the various Tribes look at this as a travesty.