Boxing in the 1920s was an exceptionally popular international sport. Many fights during this era, some 20 years away or so from the television era, were social events with many thousands in attendance, both men and women.

World Heavyweight champion Jack Dempsey dominated the sport through much of the decade. He won the title in 1919, keeping it until 1926. He lost the title to Gene Tunney in 1926, but many of his fights were historic, such as his defenses against Georges Carpentier, Luis Firpo and Tom Gibbons, a fight which almost left the town of Shelby, Montana bankrupt. His 1927 rematch against Tunney became known in boxing history as The Long Count Fight. Dempsey became a household name, and he dated and married Hollywood actresses. He was, along with Babe Ruth, Red Grange, Bill Tilden and Bobby Jones, one of the so-called Big Five of sports. Other important boxers included Benny Lynch (from West Scotland). Panama Al Brown was the first Hispanic to become a world champion.

Because airlines lacked the structured schedules of the modern days, many boxers had to make their way to important fights by train.