At boxing's beginning, the heavyweight division had no weight limit, and historically the weight class has gone with vague or no definition. During the 19th century many heavyweights were 170 pounds (12 st 2 lb, 77 kg) or less, though others weighed considerably more. John L. Sullivan was the first widely recognized champion under Marquess of Queensberry rules. Known as the "Boston Strong Boy", Sullivan weighed around 200 pounds when in shape, and helped transition the sport from its bare-knuckle era. Sullivan would be defeated for the title by "Gentleman" Jim Corbett over 21 rounds on September 7, 1892, the first heavyweight titleholder solely under Queensberry rules.

In 1920, a de facto minimum weight for a heavyweight was set at 175 pounds (12 st 7 lb, 79 kg) with the standardization of a weight limit for the light heavyweight division. The addition of the cruiserweight division, which began in 1979, reset the de facto minimum, first to 190 pounds and then to 200 pounds in 2004 when boxing's major sanctioning bodies universally raised the weight limit at which they would recognize champions. In November 2020, the World Boxing Council created a new division called bridgerweight for boxers weighing between 200 and 224 pounds, and in December 2023, the World Boxing Association followed suit. As of March 2025, no other major body has recognized the division.

The championship of the heavyweight division has been fractured or disputed at various times in its history. Until the 1960s, such disputes were settled in the ring, typically with alternate title claimants largely being forgotten. The rise of sanctioning organizations, however, have produced an environment where typically there is no single world heavyweight champion, with titleholders recognized by one of these organizations (a "World Champion") or more (a "Super Champion", a "Unified Champion", or, in the rare cases where the four most prominent organizations recognize the same boxer, an "Undisputed Champion").

Some title reigns are considered dubious owing to long periods of inactivity, the legitimacy of the organization granting championship recognition, and other factors. In 1967, for example, Muhammad Ali was denied a boxing license in every U.S. jurisdiction and stripped of his passport because of his refusal to be inducted into the armed forces. On April 29, 1967, his recognition as champion by both the World Boxing Association and World Boxing Council was withdrawn. Yet Ali remained the lineal champion and was recognized by The Ring and most boxing purists until his defeat in 1971. In pursuit of greater revenues, some organizations have now adopted a practice of simultaneously recognizing multiple champions in a weight division, creating a situation in which a champion may be unable not only to secure recognition from multiple sanctioning bodies but to secure sole recognition from a single one.

World champions were initially recognized by wide public acclamation, with heavyweight champions winning and losing championship recognition solely in the ring. Retirements periodically resulted in no one, true champion being recognized, while in other cases new champions were proclaimed only to see a previously recognized champion come out of retirement. Public interest in boxing resulted in a true champion being determined by means of title claimants facing one another in the ring, with the winner being recognized as world champion.

Currently, International Boxing Hall of Fame recognizes these world heavyweight title lineages from this period:

The Ring has recognized heavyweight champions during two periods, commencing with its inaugural issue in 1922 and continuing until the 1990s, then again from 2002 to the present day. Under its original policy, a champion earned championship recognition in the ring, defeating the preceding champion or winning a bout between its top rated contenders. Once awarded, championship recognition could be lost only by death, retirement, or loss in the ring. In 2012, this policy was revised so championship recognition could be more easily awarded or withdrawn.

The National Boxing Association (NBA) was organized in 1921 to serve as a regulating authority for boxing in the United States. The prominence of New York City as the epicenter of boxing would lead to its state boxing regulatory body, the New York State Athletic Commission (NYSAC) joining the NBA in recognizing world champions in each weight class. A third entity, the European Boxing Union (IBU) would follow suit, but with limited exception in the heavyweight division the three organizations recognized the same champion.