athlete who was the first American to win an Olympic gold medal in the 10,000-metre race, achieving a dramatic upset victory at the 1964 Olympic Games in Tokyo.

Mills, who was part Sioux, grew up on an Oglala Sioux Indian reservation and, after he was orphaned at the age of 12, attended the Haskell Institute, an Indian school in Lawrence, Kan. There and at the University of Kansas, he excelled in track events but then abandoned them for two years. While serving in the U.S. Marine Corps he returned to racing in 1964, qualifying for that year's Olympic Games in Tokyo.

Mills was a little-known entrant in the 10,000-metre run; among those favoured to win was Ron Clarke, of Australia, who held the world record. On a wet track, Mills kept pace with the leaders until the final lap, when Clarke and Mohamed Gammoudi of Tunisia forced him to the outside of a crowded field. As Clarke and Gammoudi fought for the lead, Mills, in a frantic final sprint, surged past them to win an electrifying victory by just three yards. His success continued in 1965, when he set an outdoor world record (27 min 11.6 sec) in the six-mile run and set U.S. records in the 10,000-metre and indoor three-mile races. The film Running Brave (1984) was based on his Olympic victory.