Sand Creek, Colorado, site of a massacre (1864) of Cheyenne by Col. John M. Chivington and his Colorado Volunteers. The Cheyennes, led by their chief, Black Kettle, had offered to make peace and, at the suggestion of military personnel, had encamped at Sand Creek near Fort Lyon while awaiting word from the territory's governor. There they were attacked in a surprise dawn raid on Nov. 29, 1864. Chivington and his men, choosing to ignore a white flag, slaughtered and mutilated hundreds of men, women, and children. The atrocity has been the subject of much controversy, and an effort to unearth the site began in 1998.