At one time, wrestling promoters Toots Mondt and Vince McMahon Sr controlled the Northeastern United States wrestling circuit as part of the National Wrestling Alliance. This group recognized an undisputed champion that went from wrestling company to wrestling company in the alliance and defended the belt around the world.
In 1963, Buddy Rogers was the NWA champion and his bookings were controlled by Toots Mondt. The rest of the NWA was upset with Mondt because he rarely let Rogers wrestle outside of the Northeast. It was decided that Mondt and McMahon would leave the NWA. Both wanted Rogers to keep the NWA title, but Rogers didn't want to lose his $25,000 deposit on the belt. Rogers lost the NWA title to Lou Thesz in Toronto on January 24, 1963.
In mid-April, Rogers was then awarded the new WWWF title after the WWWF claimed he won a (fictitious) tournament in Rio de Janeiro. He lost the title to Bruno Sammartino a month later on May 17, 1963 after suffering a heart attack shortly before the match.
The WWWF rejoined the NWA in 1971 and their world title was dropped to the status of a regional title.
The WWWF became the WWF in mid-1979. The name change was purely cosmetic and the ownership and front office personnel remained.
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