Dunton worked as a ranch hand as a youth and studied at the Cowles Art School in Boston, Massachusetts.

[1] In 1912 he briefly studied at the Art Student's League, where Ernest Blumenschein told him about Taos, New Mexico.

Among his proteges in Western art was Harold Dow Bugbee of Clarendon and Canyon in the Texas Panhandle.

In 1921, American oil executive W. H. McFadden commissioned Dunton to paint a full-length portrait of big-game hunter Ben Lilly.

The portrait was exhibited by the National Academy of Design before being located in McFadden's home in New Orleans.