Ivan Koloff

Perras debuted as an Irish rogue villain character named Red McNulty, billed from Dublin, Ireland and wrestling with an eyepatch.[2] For the next three years, he wrestled around the Toronto area, eventually quitting his regular job to wrestle in the north-western area of Canada. There, Perras acquired much wrestling experience, and from there he made his first trip to Japan.

In 1967, Perras became "The Russian Bear" Ivan Koloff, a bearded villainous character billed from Ukraine, and debuted with the International Wrestling Association in Montreal, Québec. He defeated Johnny Rougeau for the IWA International Heavyweight Championship the following year. Koloff debuted in the World Wide Wrestling Federation in late 1969, managed by "Captain" Lou Albano.[7] He soon started a rivalry with then-WWWF World Heavyweight Champion Bruno Sammartino. On January 18, 1971, Koloff defeated Sammartino in Madison Square Garden for the WWWF World Heavyweight Championship by pinfall after a knee drop from the top rope, ending Sammartino's seven and two-thirds years reign. Koloff lost the championship 21 days later to Pedro Morales, essentially being used as a "transitional champion" (as he was used to move the title from Sammartino to Morales without having the two fan favorites work against each other), much like Stan Stasiak and The Iron Sheik would be in later years. After the loss, Koloff remained a contender for the title but never reclaimed it, leaving the WWWF in 1971.

During his time in the WWWF, Koloff weighing in at 310 pounds (140 kg) wrestled WWWF World Heavyweight Championship title matches against Sammartino, Morales, Superstar Billy Graham and Bob Backlund, holding the distinction, with fellow villain Stan Stasiak, as one of only two men to challenge all four of these champions. Koloff would also be the first opponent to ever challenge for the WWWF World Heavyweight Championship in a steel cage match in a rematch loss against Sammartino. He fought in the WWWF from 1975 to 1976, 1978–1979 and 1983.

During the 1970s and 1980s, Koloff found success in the National Wrestling Alliance, winning many regional tag team and singles titles in the Georgia, Florida, and Mid-Atlantic territories. In February 1981, he teamed with Ray Stevens to defeat Paul Jones and Masked Superstar to capture the NWA World Tag Team Championship. This would be the first of his four reigns as NWA World Tag Team Champion, later winning the belts with Don Kernodle and twice with his "nephew" (kayfabe), Nikita Koloff as The Russian Team.

The Russians (which also included Krusher Kruschev) were a top villainous group from 1984 to 1986, and Nikita, under Perras' training and mentoring, and by association, became a hated villain in his own right, and would go on to have a successful singles career of his own. After Nikita turned on Ivan to join their enemy Dusty Rhodes in 1986, the latter teamed with Vladimir Petrov and Dick Murdoch to get revenge. Koloff's biggest NWA feuds were against Rhodes, The Road Warriors, The Rock 'n' Roll Express (Ricky Morton and Robert Gibson) and Magnum T.A..

In 1988, Koloff spent time in Paul Jones' faction, The Paul Jones Army, where he was a "coach" of sorts for The Powers of Pain, The Barbarian and The Warlord. He later split with Jones, reunited with Nikita, and feuded with Jones' team, The Russian Assassins, before leaving Jim Crockett Promotions in January 1989. In 1992, Koloff also wrestled in the first television main event of Jim Cornette's Smoky Mountain Wrestling, beating Bobby Fulton. He lost to Ron Garvin at Tim Horner's National Championship Wrestling on July 22, 1994. He retired afterwards.

He also spent time in Eastern Championship Wrestling,[7] appearing on the very first ECW card in 1992. In 1993 he began teaming with his storyline nephew Vladimir Koloff. The team won their debut match on the June 29 edition of ECW Hardcore TV. Koloff defeated The Sandman on the July 6, 1993 episode of ECW Hardcore TV in a number one contenders match for the ECW Heavyweight Championship.[8]

In 2004 Koloff returned to the ring for the first time in 10 years. He wrestled in the independent circuit.

On August 27, 2005 Koloff defeated Dominic DeNucci in a Russian chain match at WrestleReunion.

Koloff would win his final wrestling title defeating The Barbarian in a Russian chain match for the Legends title at NWA Charlotte.

On July 19, 2013 Koloff lost Shane Douglas in an Extreme Rules match at Mega Pro.

His final match was against Bob Armstrong in which Armstrong won on November 16, 2013 at Superstars of Wrestling 1 in Rome, Georgia.