Bill Polk was the son of a sheep farmer in the Old West, during a time when cattle ranchers and sheep ranchers were fighting an undeclared war. When Bill's father was murdered, everyone assumed the deed had been done by the elder Polk's cattle ranching rival, Mallon.

But Bill Polk discovered eveidence that Mallon was innocent and set out in search of the true killer, a man known as Claggett. Bill Polk's quest took him to a ranch in Texas, where he honed his skills and joined a rodeo. When he grew tired of the rodeo circuit, he joined the army as a scout, then took up prospecting. When bandits bushwacked him and stole his gold, he tracked them down and captured all three. Polk turned in the bandits and was offered a job as deputy sheriff. he turned it down, saying he preferred to travel, but not revealing his search for Claggett.

When Polk travelled, acting as a freelance deputy to sheriffs all over the West, he didn't give his real name, but went by the name, Wyoming Kid - although he also used the name Johnny Jones.

Polk took the job as sheriff of Saddlehorn for a brief time, but when he resigned once again to pursue the man who killed his father, a grateful railroad magnate - Randolph Hughes - deposited money in banks around the west so the Kid always had funds to draw on. It was never recorded whether the Wyoming Kid ever found his father's killer.