Richard Harris stars in this carefully documented epic that attempted to realistically portray the life of the American Sioux in the early 19th century. When an English lord is captured by a Sioux Indian tribe, he is given to the chief's aging mother (Dame Judith Anderson) as a servant. Gradually, he embraces the tribe's way of life and falls in love with the Cheif's sister. But before he can be accepted with honor as an equal member of the tribe, he must endure the Sun Vow - a savage ritual far beyond the realm on anything dreamed of in the civilized world.

To recreate authentic Indian costumes for the film's accuracy, the production designer met with real American Indians only to discover their notion of Indian clothing was based on the costumes designed by Hollywood studios.

In 1825, John Morgan (Richard Harris), an English aristocrat, is captured by a tribe of Sioux Indians. Hoping to save his own life by proving his worth, Morgan undergoes the long, painful Sun Vow ritual, where he is hung in a tree by the flesh of his chest. This film, which paints a very detailed portrait of the Sioux customs and lifestyle, spawned two sequels: RETURN OF A MAN CALLED HORSE and TRIUMPHS OF A MAN CALLED HORSE.