It all began on Nov. 12 during UFC 1 at Denver’s McNichols Arena, where Royce Gracie (R) forever altered the worlds of martial arts and combat sports by submitting Art Jimmerson (L), Ken Shamrock and Gerard Gordeau in one night to win the open-weight, no-time-limit, limit-rules tournament and $50,000. (Photo by Markus Boes)

The UFC put on three events in 1994 as buzz began to build about the product. The most memorable was UFC 3, the first real hint of MMA’s utter unpredictability: Alternate Steve Jennum, an Omaha policeman who ended up with a career record of 2-3, won the Sept. 9 tourney in Charlotte by defeating Harold Howard as a substitute for Shamrock. (UFC.tv screen shot)

The peak of the early days in the face of impending backlash was UFC 5 in Charlotte on April 7. A non-tournament superfight between Gracie (L) and Shamrock (R) drew 250,000 pay-per-view buys, a record which would stand a decade. The bout itself was a dud, with the duo grappling to a 36:06 draw, the longest fight in UFC history. (UFC.tv screen shot)

The UFC pressed on in the face of political headwinds. UFC 10 on July 12 Augusta, Georgia, featured the debut of “The Godfather of Ground ’n’ Pound,” Mark Coleman, who won three fights to claim a tournament victory. The future UFC Hall of Famer would also go on to win the UFC heavyweight title and a PRIDE Grand Prix. (UFC.tv screen shot)

Venues and PPV distributors continued to back out, but smaller-scale UFC events were the platform for the debut of legendary names. Like at UFC 12 on Feb. 7 in Dothan, Alabama, where 19-year-old Vitor Belfort (R) needed just two minutes flat to win his pair of fights and claim the heavyweight tournament in his UFC debut. (UFC.tv screen shot)

The UFC put on just three events in 1998. The most memorable was UFC 17 on May 15 in Dothan, Alabama, which featured the UFC debuts of two legends: Chuck Liddell earned a decision over Noe Hernandez in his MMA debut; while Dan Henderson (pictured) earned decisions over Allan Goes and Carlos Newton to claim the middleweight tournament. (UFC.tv screen shot)

The greatest fight of MMA’s dark era and one of the first true classics of the sport went down at UFC 22 on Sept. 24 in Lake Charles, Louisiana, where Frank Shamrock (L) won a grudge match with Tito Ortiz to retain the middleweight (now light heavyweight title) via submission in a four-round war. (UFC.tv screen shot)

The final event under original UFC owners Semaphore Entertainment also provided a glimpse into the sport’s future. UFC 29 in Tokyo on Dec. 16 featured successful title defenses by Ortiz (R) over Yuki Kondo (L) and Pat Miletich over Kenichi Yamamoto, as well as appearances by future UFC champs Liddell, Evan Tanner and Matt Hughes. (UFC.tv screen shot)

It was a pivotal year behind the scenes, as casino magnates Frank (L) and Lorenzo Fertitta (R) bought the UFC, installed Dana White (C) as president, and were sanctioned in Nevada. But their coming-out show, UFC 33 in Las Vegas on Sept. 28, was memorable for all the wrong reasons, as all three title fights went to dull decisions and the PPV broadcast cut off before the show ended. (Associated Press)

2002: The first fight to gain some mainstream traction in the modern era was the grudge match between Ortiz (L) and Ken Shamrock (R) at UFC 40. A crowd of 13,265 in Las Vegas paid a gate of $1.5M and PPV buys cracked 100,000 for Ortiz’s successful defense of his light heavyweight belt, won by corner-stoppage TKO after the third round. (Photo by Josh Hedges/Zuffa LLC/Zuffa LLC via Getty Images)

In the start of a legendary trilogy, Randy Couture (L) TKO’d Liddell (R) in the first round of their UFC 43 bout on June 6 in Las Vegas to claim the interim light heavyweight belt. That made former heavyweight champ Couture, who later defeated Ortiz to win the full title, the first man to hold two UFC weight-class belts. (Photo by Josh Hedges/Zuffa LLC/Zuffa LLC via Getty Images)

Another feud kicked off at UFC 47, where Liddell (R) knocked out former training partner Ortiz (L) in the second round of a highly anticipated light heavyweight bout in Las Vegas on April 2. Liddell won their rematch in December 2006 via TKO and they will incredibly rematch again under the Golden Boy promotions banner later on Nov. 24. (Photo by Josh Hedges/Zuffa LLC/Zuffa LLC via Getty Images)

“The Ultimate Fighter” reality series on SpikeTV broke the UFC through to the masses. The first TUF Finale, on April 9 in Las Vegas, saw three million viewers tune in for a legendary slugfest in which Forrest Griffin (R) earned a unanimous decision over Stephan Bonnar (L) to win the light heavyweight tournament. Diego Sanchez won the middleweight tourney with a TKO of Kenny Florian. (Photo by Josh Hedges/Zuffa LLC/Zuffa LLC via Getty Images)

The UFC exploded in popularity in 2006. Few events were bigger than UFC 60, when welterweight champ Matt Hughes (R) met the returning Gracie in a non-title fight on May 17 in Los Angeles. A record 620,000 PPV buys were recorded as old-school fans returned to see the new school take over, as Hughes scored a first-round TKO. (Photo by Gregg DeGuire/WireImage)

Liddell (R) had peaked in pop culture as light heavyweight champion, making appearances on shows like “Entourage” and gracing the cover of ESPN magazine. This made his UFC 71 bout with Quinton Jackson (L) a giant deal, but “Rampage” spoiled the party on May 26 in Las Vegas with a KO win in just 1:53. (Photo by Josh Hedges/Zuffa LLC via Getty Images)

The UFC’s Canadian debut, UFC 83 on April 19 at Montreal’s Bell Centre, was one of the loudest and most raucous nights in company history. Hometown hero Georges St-Pierre (L) avenged an upset loss to Matt Serra (R) via TKO in the main event, kicking off a welterweight title reign which would last five years and eight months. (Photo by Josh Hedges/Zuffa LLC via Getty Images)

UFC 100 was regarded as the peak of the first modern boom era. Brock Lesnar (L) avenged a loss to Frank Mir (R) and unified the heavyweight title via second-round TKO on July 11 at Mandalay Bay in Las Vegas. The card sold 1.6 million PPV buys, a company record which stood until the heyday of Conor McGregor. (Photo by Jon Kopaloff/Getty Images)

The legend of Anderson Silva (R) was set for life at UFC 117 on Aug. 7 in Oakland. Silva took a beating for four-and-a-half rounds from Chael Sonnen (L) before baiting him for the most dramatic submission win in company history, saving his middleweight belt with a triangle arm bar. Silva’s seven-year, seven-month reign as champ remains the longest in UFC history. (Photo by Josh Hedges/Zuffa LLC/Zuffa LLC via Getty Images)

A record 55,724 paying a gate of $12 million USD, both North American MMA records, showed up at Rogers Centre in Toronto for the UFC’s first-ever event in Ontario. In the main event, Canada’s Georges St-Pierre (R) retained his welterweight belt via unanimous decision over Jake Shields (L). (Photo by Al Bello/Zuffa LLC/Zuffa LLC via Getty Images)

A grudge match between former friends and training partners Jon Jones (L) and Rashad Evans (R) captures the public’s imagination as the duo squared off in the main event of UFC 145 in Atlanta. Jones’ unanimous-decision victory to retain his light heavyweight title marked his fourth straight win over a former world champion. (Photo by Al Bello/Zuffa LLC/Zuffa LLC via Getty Images)

The historic UFC 157 on Feb. 23 in Anaheim, California, marked the first women’s fight in UFC history. Ronda Rousey, who had been Strikeforce champ, retained her newly created UFC bantamweight title over openly lesbian challenger Liz Carmouche in the main event, ushering in an era that now features four UFC women’s weight classes. (AP Photo/Jae C. Hong)

While Rousey’s star rose, so too did that of brash Irishman Conor McGregor. “The Notorious” had his first UFC main event on a memorable July night in Dublin. Irish fighters went 5-0 on the evening, culminating in McGregor bringing the roof down at sold-out O2 Arena with his first-round win over Diego Brandao. (PA Images)

Rousey became a breakthrough, mainstream superstar, but it all came crashing down at UFC 193. A crowd of 56,214 in Melbourne, Australia saw Holly Holm dominate Rousey, then finish her with a head kick in the second round. Rousey fought just once more before fleeing to the safety of the WWE’s scripted fighting. (Photo by Quinn Rooney/Getty Images)

This was the year of McGregor. McGregor, who started the year as featherweight champ, split a pair of welterweight fights with Nate Diaz, then became the first simultaneous two-weight champ in UFC history with his second-round TKO of Eddie Alvarez to claim the lightweight belt at UFC 205 in Madison Square Garden. (Photo by Michael Reaves/Getty Images)

After being away from the sport nearly four years, St-Pierre (L) returned and joined the ranks of two-weight class champions. GSP took a beating from Michael Bisping (R), but roared back to submit him in the third round and claim the middleweight title at UFC 217 at Madison Square Garden. (Photo by Mike Stobe/Getty Images)

A real-life grudge between McGregor and Khabib Nurmagomedov led to the biggest fight in UFC history. McGregor’s antics before the fight led to revenge for the Russian at UFC 229, who submitted him in the fourth round to retain the lightweight title, then started a brawl which got worldwide headlines. An estimated 2.4 million people tuned in on PPV. (Photo by Harry How/Getty Images)