Edited sentence: Bob Fitzsimmons, first heavyweight champion from the UK.Evander Holyfield first cruiserweight champion to capture the heavyweight title, first heavyweight to capture a sanctioning body belt four different times.Floyd Patterson, the first heavyweight champ to regain the title, youngest undisputed champion and second youngest title claimant.Gene Tunney.George Foreman, who reclaimed the championship after a 10-year retirement to become the oldest heavyweight champion at 45.Jack Dempsey.Jack Johnson, the first African-American heavyweight champion.James J.Jeffries, won undisputed title in his 12th fight.Jim Corbett.Joe Frazier.Joe Louis, who defended the title a record number 25 times.John L.Ken Norton.Larry Holmes defended title 20 times.Lennox Lewis, the first British champion in 100 years.Max Baer.Max Schmeling only undisputed heavyweight champion to win the title by disqualification.Michael Moorer first left-handed heavyweight champion.Michael Spinks, first light heavyweight champion to ever capture a heavyweight title.Mike Tyson, youngest champion, first undisputed champion to hold the three sanctioning body belts.Muhammad Ali, first to hold the heavyweight title three separate times.Nikolai Valuev, tallest and heaviest champion.Riddick Bowe.Rocky Marciano, the only heavyweight champ to retire undefeated.Ruslan Chagaev, current WBA heavyweight champion.Sonny Liston.Sullivan, first heavyweight champion under modern rules.Vitali Klitschko, knockout percentage of 92%, highest of any heavyweight champion.Wladimir Klitschko