Longest time between world heavyweight boxing titles

The longest time between the same boxer holding world heavyweight titles is 20 years and 7 days. George Foreman (USA, b. 10 January 1949) won the world heavyweight crown on 22 January 1973 against Joe Frazier (USA) in two rounds at the National Stadium in Kingston, Jamaica. He then lost this title when he was knocked out in round eight on 30 October 1974 in Stade du 20 Mai, Kinshasa, Democratic Republic of Congo, by Muhammad Ali (USA). Foreman regained the WBA and IBF versions of the championship on 5 November 1994 when knocking out title holder Michael Moorer (USA) in round 10 in Las Vegas.