Lou Thesz, the second champion of the National Wrestling Alliance starting as it went into its second year in 1949. He was considered the first "World" Heavyweight NWA Champion because he traveled around defeating other claimant world champions and unifying their titles with his own, gaining the recognition of their companies. It's been expected of world champions in the NWA to tour the territories/member promotions and defeat the local champions in their division since and no one has come close to Thesz's status as "undisputed" world champion since he retired.
After Rikidozan defeated Lou Thesz for the NWA International Heavyweight Title he went on to hold the belt for five years until his death at the end of 1963. Even then, He handed his assassin his own ass after being stabbed, only dying due to an infection as the blade had been pissed on. Rikidozan is in fact the source of the word "ace" as it was used in wrestling from then on.
Bruno Sammartino was WWWF (the entity that would later morph into WWF and WWE) World Heavyweight Champion for over seven and a half years. 2803 days Sammartino held the title, the longest of any wrestling championship on record. In this day and age of frequent title changes for TV and wrestlers taking time off to heal from injuries rather than working through them? It's unlikely this will ever happen again. Only two other reigns log half of Sammartino's streak:
Bob Backlund held the title for 2135 days between 1978 and 1983 (the reign was technically interrupted by Antonio Inoki, however WWE officially considers the run uninterrupted).
Hulk Hogan held the title for 1474 days between 1984 and 1988.
For comparison, the longest reign since Hogan's was CM Punk's 434 day reign spanning 2011-2013, not even 1/5 as long as Sammartino's legendary run.
El Canek, starting in 1978 when he defeated Lou Thesz and won the Universal Wrestling Association's World Heavyweight title belt. He was so popular in Mexico that UWA could coast on Canek beating people for another ten years. Never could beat Mil Mascaras though.
Ric Flair is widely considered the best wrestler of all time in terms of drawing money, performance, and legacy. The only other guys who even make the debate are Bret Hart, Shawn Michaels, Mitsuharu Misawa and "Stone Cold" Steve Austin. Michaels and Austin both openly say Ric was the best. There are legions of pro wrestlers who followed who cite Flair as their favorite wrestler. Officially he has sixteen recognised World Title reigns, a mark that stood alone until John Cena tied it in 2017. Flair claims 23, citing times a title change was not televised.
Mitsuharu Misawa is widely considered to be one of if not the greatest in ring performers in Japanese pro wrestling history. The man was the undisputed ace within AJPW during the 1990s, and holds the Wrestling Observer record for five star matches.
Hulk Hogan, starting in 1984. Whenever he would perform his "Hulk Up" maneuver, did he ever fail to block an opponent's punch?
In 1989, Big Van Vader won the Catch Wrestling Association World Heavyweight Title in Germany, The International Wrestling Grand Prix Heavyweight Championship in Japan and the Universal Wrestling Association World Heavyweight Championship belt in Mexico, traveling between three continents to defend the three belts. Vader was the closest thing Professional Wrestling ever had to a true world heavyweight champion. As far as "world titles" go, he has had thirteen separate reigns, so there is that too.
The Undertaker is the ultimate McMahon wet dream: he's big and strikes an imposing figure, but also has the in-ring chops and mic skills to back up the hype. So naturally the respectable intimidating but beatable redhead from Texas became a monster as scary as death from his first WWF match in November of 1990 onward. Hell, during his heyday back in the late '90s, the man was unbeatable, and he was capable of going toe-to-toe with just about every wrestler and style out there. As further proof, he was still putting on matches that are rightly regarded as instant classics well into his 40s. See both his matches against Shawn Michaels, his match against CM Punk in 2013 and the match against Brock Lesnar that ended his undefeated streak. In the WWE, only Chris Jericho and the aforementioned Shawn Michaels can boast of being able to carry out matches as good as some of the ones The Deadman has pulled off at similar ages.
In a fed known for short title reigns, La Tigresa began a five year reign as the CSP/WWC Women's champion in 1993. She is the first woman wrestler from Puerto Rico to became a star in Puerto Rico itself and among critics is a contender for best women's wrestler to ever come from island.
Though he was nicknamed "Fatso" by detractors, Kurt Angle was the first person Cauliflower Alley Club declared to be a "Future Legend", as he started to gain a reputation as being just that good in 1995 after he won a gold medal in at The Amateur World Championships in Atlanta. He truly cemented it next year in 1996 when he won an Olympic Gold Medal despite suffering a broken neck in the preliminaries. Oh and despite his "fragile" body he can easily suplex much larger professional wrestlers like The Big Show. Oh its true, its damn true!
In 1996 Ultimo Dragon became the most decorated professional wrestler of all time. Not in total number of titles ever won but total number of belts held in a single period. He was the active reigning and defending champion of ten titles! Like Vader, these included belts of promotions on three different continents, though Dragon was a cruiser weight (or junior weight, or welter weight, middleweight, light heavyweight-he held belts in all those divisions)
Kazushi Sakuraba, after making the jump from professional wrestling to mixed martial arts, became the first person to ever hand one of the Legendary Gracie brothers a defeat in a professional fight and went on to defeat four of them and become champion of UFC Japan. Even after injuries stunted his mixed martial arts career, he was pretty much set as a professional wrestler (and there is much less distinction between the two in Japan anyway, in part because of his and trainer Nobuhiko Takada's efforts in both fields)
In WCW, cases could be made for Sting or Ron Simmons but the wrestler best known to simply win all the time and be comically invincible was Bill Goldberg, who from his debut in June of 1997 up until December of the next year won 173 matches in one streak, even going through the seemingly unstoppable nWo(at first, anyway).
Mariko Yoshida's 1998 repackaging in ARSION did away with her fancy high flying but kept all the intricate Lucha Libre type submissions in addition to taking on a more catch based style and get billed as the best wrestler in Japan (or at the very least, best female wrestler). She spent the next 17 years playfully stretching people out the world over.
After Toryumon Mexico spun off from IWRG, it found an ace by 1998 in CIMA, who became the first holder of the Ultimo Dragon Gym title. While many Toryumon wrestlers ended shoved into the Japanese branch's background by new acquisitions when it became Dragon Gate, CIMA continued to rise, his gimmick becoming the ability to counter anyfinishing move, which means more than usual given how many new ones come from the Toryumon\Dragon Gate rosters.
Once reluctant wrestler Carly Colón actually got some proper training in 2000, he quickly caught on, defeating every member of La Familia del Milenio available to fight him and forcing Ray González to seek off island help after Carly proved to difficult to keep the WWC Universal title belt away from. Mr. Perfect Curt Hennig, himself an example, eventually got the job done only for Carly to win the Universal title back five days later.
Bryan Danielson (That's DANIEL BRYAN for all you WWE Fans) won All Pro Wrestling's second "King Of Indies" in 2001 and made the most of the title out of all the KOIs. From 2005 he won The Wrestling Observer Newsletter's "Most outstanding wrestler" award eight years in a row, the "Best technical wrestler" award four years in a row after 2006 and most outstanding of the whole decade by its end, largely voted best of his generation by his own peers. 2005 was also when he started to believe his own hype in Ring of Honor and proceeded to live up to it by winning both of its singles titles and that of sister promotion FIP. He's gotten over pratically everywhere he's gone, being a champion in ASW of the UK, wXw of Germany, WSW of Australia, IWA Puerto Rico, NOAH of Japan, and ECCW of Canada to name a few and when he proclaimed to no longer be the best in the world after his (presumed) final Dragon Gate USA in 2009 the fans disagreed with him.
Kyra's gimmick in EWF and UPW was that of a woman who had shot to the top of every activity she had ever partaken in, starting with tiger cub wrestling when she was three years old to the CIA in her late teens and now wrestling in her mid twenties(with beauty contests somewhere in between). However, this only extended to those two promotions and a handful of others in the Western USA. Elsewhere, such as WWA Tijuana, the likes of Caged Heat's Loca and Ayako Hamada used Kyra as a punching bag.
In 2002 The Briscoe Brothers were Tag Team Champions of JAPW, PWF and NWA Wildeside at the same time, which was just the start. Twelve years after Ring of Honor established their first title belt there had only been two men to hold their world title twice, one two time television champion and no champions who ever successfully regained the Pure Championship belt. In sharp contrast, The Tag Team Title belts had been won by The Briscoes seven times during this time period and Dem Boys would start an eighth reign at the end of the year. Some of their ROH reigns also overlapped with their winning the tag titles of sister promotion Full Impact Pro, Ruckus's RCW, Pro Wrestling Unplugged, 2CW and the GHC Junior Heavyweight Tag Titles of Pro Wrestling NOAH. They later became IWGP Heavyweight Tag Team Champions, after being the inaugural NEVER Openweight 6-man Tag Team Champions alongside Toru Yano. While The Briscoes don't dominate singles matches the same way they do as a tag team, Jay was the second of those two men to regain the ROH World Championship belt.
AJ Styles in the International Wrestling Cartel, despite never being a full time member thanks to his loyalty to TNA and TNA's tendency to mettle in things, was the first man to be part of the "match of the year" three years in a row and has never actually lost the IWC Super Indy Championship belt in a match. The only man tougher in IWC than AJ Styles is Abyss, who has never lost a match hosted by the Cartel. AJ Sytles is also the only wrestler to have ever won ALL SIX of the championship belts ever made eligible for Triple Crown and/or Grand Slam status in TNA history.
Mike Quackenbush defended six belts from three different countries, Mexico, USA and Germany all at once in 2004. In fact, one could argue he was the ace of Chikara for the first nine years of its existence, and can't argue at all that he was the ace among the tecnicos.
John Cena, 2005 onward, who somehow manages to "win" even when he loses. Which he rarely does. His 2015 renaissance showed he has it in him to be one for real as well, putting on quality matches with just about anyone he wrestled.
The Kings Of Wrestling in between 2005 and 2006 were the aces of tag team wrestling in the USA. They held the CZW, Ring Of Honor and Chikara tag team title belts all at once and only really dropped the belts because WWE was interested in Castagnoli, only to abruptly drop him, allowing the Kings to reform up until WWE finally found something for Castagnoli to do. This was not the case in Japan however, where the Kings entered Pro Wrestling NOAH's Global Tag League and lost all of their matches in 2008. In 2010 they cemented themselves as such with an ROH tag team title reign longer than even The Briscoes managed and even got a little winning streak started in Japan but when they tried NOAH's Global Tag League again in 2011, they merely placed 7th out of 8 in the round robin.
2007 was the year of Dos Caras Jr, where he went on to win the CMLL Heavyweight title belt and held it until the last three days of 2008 when he got an offer with WWE. Since leaving WWE, El Patron Alberto, as he came to be known, became the World Heavyweight Champion of both AAA and The World Wrestling League in 2015, he did this after the two's working relationship ended.
Irish Airborne in the International Wrestling Cartel's tag team division from the start of 2009 till mid 2010 where they not only held the tag team championship belts for fifteen months but Dave and Jake Crist also put the former aces, Sexual Harassment, on the shelf. Just in the tag team division though, as they were lackeys otherwise.
Sara Del Rey in Jersey All Pro Wrestling after she won their Women's Championship belt 2009 and went on to hold it for the next three years with JAPW having to go out and find more challengers after she beat all they had and her reign only ended due to her WWE schedule interfering with defenses. She had defenses in the main event too.
Eddie Kingston, after he decided Die Bruderschaft des Kreuzes needed to be defeated. He went on to become the first Chikara Grand Title holder and held onto it for three years, going into a sort of Heroic Blue Screen of Death when he lost it Icarus.
TNA's fans voted for Austin Aries as the wrestler they most wanted to see TNA sign and they got their wish in 2011, where he won the X Division title belt and proceeded to defeat every single wrestler in the division, to the point TNA decided to give up on getting him challengers and asked him to drop the belt and compete in a different division. This ended up being defied by Samoa Joe, who while X division champion after Aries dropped the belt again, challenged Aries, or rather, demanded Austin Aries challenge him, and then successfully retained the belt.
2011 was the year that really established Hailey Hatred in Japan. With help from Queens Revolution partner Kaori Yoneyama she held onto the TLW world tag team titles, Daily Sports Tag Team Titles, Japanese Women's Pro Wrestling Project Tag Team Titles, TLW World Women’s Singles Title, Japanese Women's Pro-Wrestling Project Open title and IMW Hybrid Fighting all at once. She'd further cement her legacy in 2012, as though she lost some belts, Hatred still ended up holding onto six at once by the end of the year, IMW Hybrid Fighting, the International Ribbon Tag Team titles, the Reina World Tag Team titles, the Remix Pro Women's Championship belt, the TLW World Women's title and a Triangle Ribbon Championship belt, this time holding belts based in the USA and Mexico in addition titles of Japanese promotions.
Okada Kazuchika was declared Shin Hein Jidai no Ace by New Japan Pro-Wrestling following his return from TNA, acquisition of IWGP Heavyweight Championship and naming of MVP of the professional wrestling business by Tokyo Sports in 2013. In a bout of Critical Dissonance the fans voted Hiroshi Tanahashi to be the ace of New Japan, so New Japan listened and put Tanahashi higher on the card.
reDRagon. While Bobby Fish had some tag success back in his Jerk Jackson days, Kyle O'Reilly only found it in singles junior heavyweight matches and only on a regional basis. But after numerous failed tag teams O'Reilly partnered with Fish in 2013 and went on to boast an undefeated streak against the faces of what had become the deepest tag team division in the world, The Briscoes. reDRagon then did No Remorse Corps(who lent credibility to that claim in a takeover of New Japan's Junior ranks) and Forever Hooligans(the first to hold IWGP and ROH tag titles at the same time) better by taking the IWGP Junior Heavyweight Tag Titles without contracts. This eventually bled into their singles careers, as both members of reDRagon ended up as singles champions of ROH in the same year, though their reigns were not simultaneous.
The Outlaw Wrestling Federation's champion in 2014, Captain All-American Chris Alexander, boasted a reign of twelve consecutive years (among other things).
After four years of mostly losing, Drew Galloway found success again in the WWN when he became Evolve Champion near the end of Summer 2014. Spring of next year he was still in the WWN, still champion, also won The Open The Freedom Gate. His momentum then took him to Australia, where he took the Outback Championship Wrestling Heavyweight title, then back to his native Scotland where he regained and proclaimed the Insane Championship Wrestling Heavyweight belt a world title. He further cemented himself in Scotland by winning the heavyweight belt recognized by both the Scottish Wrestling Alliance and NWA UK Hammerlock then got yet more gold in Denmark by taking the Danish Pro Wrestling Heavyweight title.
After TNA went into hibernation in November 2014, Santana Garrett strolled back into her old stomping grounds and ran through the reigning champions at an alarming rate, getting back Southern Championship Wrestling's Women's title, plus getting NWA World Women's, Ring Warriors Battling Bombshells, SHINE, Jersey Championship Women's and Coastal Championship Women's Title wins. She'd then go on to become the inaugural holder holder of the CWE Vixen, Orland Pro Women's and Nova Pro Women's championship belts. In between she teamed up with Chasyn Rance to take Belleview's Tag Team belts, establishing herself as the queen of Florida and possibly the entire US independent circuit. Then in 2015, she lost the two most prestigious belts in her collection but took the Wonder Of STARDOM in Japan. Midway into 2016 her streak hadn't slowed.
During Garrett's reign as SHINE Champion The Kimber Bombs were also carrying multiple belts, having SHIMMER's tag titles in addition to SHINE's, Cherry Bomb being WSU Champion and IWIW Champion, Kimber Lee also being a WSU tag team champion with Annie Social and a Legacy Wrestling Women's Champion.
The British Messiah Timothy Thatcher hit his stride during 2015. Already approaching two years as a Golden State tag team champion with his rival and worthy opponent Old School Oliver John in Wrestling Cares Association, he picked up another tag team title with Drew Gulak in Championship Wrestling From Hollywood. Then he defeated Drew Galloway for both the Evolve and Open The Freedom Gate Titles.
While Thatcher was overseas, the ace of the UK itself was Pete Dunne. By 2016 he had been The Pro Wrestling Kingdom Champion for three years and there was scarcely a time during the year he wasn't holding at least five title belts, the others being of Fight Club Pro, Progress Wrestling(both singles and tag team with Trent Seven), Kamikaze Pro, ATTACK!(their 24/7 title no less), and VII Pro. Though he wasn't strictly limited to the UK, as Dunne also had Ireland's OTT, and the wXw Shotgun belt during this time period.
Dramatic Dream Team: HARASHIMA is known as "King Of The Indies" as was the ace of DDT for a long while.
Asuka debuted as this in NXT in 2016. She steamrolled a few opponents early on and won an opportunity to take on NXT Women's Champion Bayley whom she then beat. She went on to hold the title for 510 days, racking up an undefeated streak of 185 wins (that still stands as of 09/15/17). She only relinquished the title because she got called up to the main roster.