Soldier Blue

Soldier Blue is a 1970 American Revisionist Western movie directed by Ralph Nelson and inspired by events of the 1864 Sand Creek massacre in the Colorado Territory. The screenplay was written by John Gay based on the novel Arrow in the Sun by Theodore V. Olsen republished as Soldier Blue after the movie was released. It starred Candice Bergen, Peter Strauss and Donald Pleasence.

Eventually, after being shot at by a white man who supplied guns to the Indians, Honus finds himself alone in a cave where Cresta leaves him to get help. She arrives at Fort Reunion, only to discover that her fiances cavalry plans to attack the peaceful Indian village of the Cheyenne the following day. She runs away on a horse and reaches the village in time to warn Spotted Wolf, the Cheyenne chief. The chief refuses to indulge in warfare and rides out to extend a hand of friendship to the American soldiers using the U.S. flag. The soldiers, however, obey the orders of their commanding officer to open fire at the village. After a cavalry charge decimates the Indian men, the soldiers enter the village and begin to rape and kill the female survivors as Honus attempts to disrupt the massacre. Cresta attempts to lead the remaining women and children to safety, but her group is discovered and massacred while Cresta herself is spared. After the battle, Honus is led away in shackles and Cresta departs with the remaining survivors.The movie provided the first motion picture account of the Sand Creek massacre, one of the most infamous incidents in the history of the American frontier, in which Colorado Territory militia under Colonel John M. Chivington massacred a defenseless village of Cheyenne and Arapaho on the Colorado Eastern Plains. ........

Source: Wikipedia