One of the world's greatest heavyweight boxers, William Harrison "Jack" Dempsey (1895-1983) was so popular that he drew more million-dollar gates than any prizefighter in history.

William Harrison Dempsey, more commonly known as "Jack" after age 20, was born in Manassa, Colorado, on June 24, 1895, the ninth child of Hyrum and Cecilia Dempsey, both sharecroppers. The family was so poor that Jack began farming at the age of 8. From age 16 to 19 he lived in hobo jungles.

Dempsey's early boxing often took place in back rooms of frontier saloons under the name "Kid Blackie." His first fight of record was in 1915 against "One-Punch" Hancock. Dempsey's one-punch win earned him $2.50; his highest purse. Eleven years later his purse was $711,000 for his first match with Gene Tunney. Eventually called the "Manassa Mauler," Dempsey earned more than $3,500,000 in all in the ring.

Dempsey's appeal lay in his punching ability: he was a ruthless tiger...