When the Ultimate Fighting Championship débuted in late 1993, no one ever imagined that they would be creating a new sport. The term 'Mixed Martial Arts' had not even been coined yet. The only thing that has remained consistent in the more than two decades since UFC 1 is the eight-sided cage and its name - The Octagon.

The original purpose of the UFC was to answer the question that had been asked by fans and fighters for decades - which martial art is superior? UFC co-founder Art Davie had the idea to create a tournament that would feature several different styles of martial arts and fighting systems going against each other in no-holds-barred competition when he had seen a video series on the Brazilian Gracie family that showed them taking on fighters of various disciplines, heights, and weights and defeating them with their brand of Jiu Jitsu, Brazilian Jiu Jitsu. This style was so closely associated with the Gracie family that it was sometimes referred to as Gracie Jiu Jitsu. The Gracie family firmly believed that their brand of Jiu Jitsu could defeat any other fighting style, and the size of the fighter was irrelevant. These early tournaments proudly declared "There are no rules!". Fights typically ended quickly, decisively, and often violently. Injuries were common.

Aside from the criticism regarding the violence of the sport, another early criticism was that some fighters believed that the rules were skewed to favour co-founder Rorion Gracie's younger brother, Royce, who had won the first two tournaments and the fourth. Hall of Fame member Ken Shamrock alleged that he was told he couldn't wear his shoes in the Octagon as they could be considered a weapon, to which he was alleged to have asked what the organisers considered Royce's gi, which he frequently used to choke fighters. It has also been noted that in the earliest days of the UFC, few fighters had any ground fighting experience, with allegations that fighters were hand-picked as a way of "proving the superiority" of Gracie Jiu Jitsu. The allegation gained momentum after UFC V, when the Gracie family sold their interest in the UFC as the event was just beginning to incorporate stricter rules in order to appease state athletic commissions. Just because the Gracies left, however, their influence was still felt, as more and more fighters would begin to incorporate Jiu Jitsu into their fighting styles. In the present day, it is virtually impossible to find success in the UFC without some knowledge of ground fighting techniques.

The violence of these early years would capture the attention of several politicians, most notably Arizona Senator John McCain, who would denounce the sport as "human cockfighting". McCain and other politicians would use their influence to encourage state athletic commissions to ban the UFC in their states, and the UFC was soon banned in all states having a state athletic commission.

Despite attempts at greater cooperation with state athletic commissions to receive sanctioning, which would later evolve into the creation of the Unified Rules of Mixed Martial Arts, the UFC's reputation for brutality and violence would precede it, and the promotion would be unable to secure the large venues of the past for their shows, forcing them "underground" by their own reputation. Last minute venue cancellations were not uncommon. The UFC had the same uphill battle against pay-per-view carriers, who similarly shunned the sport, refusing to air it due to concerns over the content. The last several shows under the fight company's original ownership, Semaphore Entertainment Group (SEG Sports), would never even see a home video release until after the UFC was sold. The UFC then took their product overseas to Japan, where Mixed Martial Arts was becoming popular with the rise of the K-1 kickboxing group that began around the same time as the UFC and the PRIDE Fighting Championship, which started in 1997. The goal was attempting to open a separate, Japanese-run version of the UFC. The idea ultimately did not succeed due to the competition faced by the home-grown Japanese fighting companies as well as the ongoing financial pressures faced by the UFC stateside.

Olympic gold medallist, former UFC commentator, and (then) UFC Commissioner, the late Jeff Blatnick, was a key figure in getting both the California and New Jersey State Athletic Commissions to pass the "Unified Rules of Mixed Martial Arts" in 2000, which were co-written by Blatnick, UFC matchmaker Joe Silva, and UFC senior referee, "Big" John McCarthy. The goal of creating these rules were to not only appeal to sanctioning bodies, but to also overcome the reputation the UFC had for violence. Blatnick travelled around the country, using his status as an Olympic gold medallist to lend legitimacy to the sport, and in November, 2000, the UFC was able to run their first show in New Jersey, UFC 28: High Stakes, the very first show sanctioned by the New Jersey State Athletic Control Board, held under the newly formed Unified Rules of Mixed Martial Arts, and airing from the Trump Taj Mahal in Atlantic City, New Jersey, the first event held in a northern state. The new sanctioning introduced strict new weight classes, similar to boxing. No more would you find a 185 pound man fighting someone literally three times his weight, as well as standardising the gear worn in the Octagon: gloves, trunks, and shoes (shoes would later be removed from the rules). UFC 28 introduced fans to (soon to be) popular fighters Andrei Arlovski, Renato "Babalu" Sobral, Josh Barnett, and Gan McGee and also marked the first and only UFC Super Heavyweight bout between Josh Barnett and Gan McGee.

Despite the success of the UFC gaining sanctioning in two states, the battle was far from over, as the UFC was still very much a tarnished brand, and success in restoring credibility to it would be a long road, and SEG Sports was still losing money.

The struggle to keep the UFC afloat in these difficult times proved to be too much for SEG Sports, and by the end of the decade, they were near bankruptcy. Future UFC President Dana White heard of the impending bankruptcy, as he was managing (future) UFC Hall of Fame fighters Tito Ortiz and Chuck Liddell at the time. He, in turn, contacted Las Vegas casino executive Lorenzo Fertitta, who also was a member of the Nevada State Athletic Commission, and convinced him to enquire if the UFC was for sale. Lorenzo and brother Frank III purchased the UFC in January 2001 for a reported two million dollars, creating a new company, Zuffa, LLC, to manage its assets. Fertitta would comment in an interview to Fighter's Only Magazine in 2009 that his attorneys felt he was "crazy" to spend two million dollars when there were few assets that he would be receiving for his money, but Fertitta replied that the most valuable asset he could possibly acquire from SEG would be "those three letters: UFC", indicating that even if you didn't necessarily like the UFC, you still recognised the brand, and Fertitta knew if he could build the damaged brand back up, he could succeed with it.

Having run a successful event in New Jersey, which was attended by key members of the Nevada State Athletic Commission, started the ball rolling in a positive direction. This at least gave UFC, after it was purchased by the Fertitta brothers in early 2001, the ability to run shows in Atlantic City, as well as the Meadowlands in East Rutherford, N.J., while being regulated by a major athletic commission. Fertitta's status as a former member of the Nevada State Athletic Commission enabled him to secure sanctioning in the state in 2001, but there was still much work to do if they wanted to remove the sport's damaged reputation in order to forge ahead with a new direction.

Despite the success of UFC 40, long-term success still eluded the UFC, as it was still experiencing financial difficulties. By 2004, a mere three years after Zuffa had purchased the UFC, the company reportedly posted some thirty-four million dollars in losses. Faced with the prospect of folding the UFC, Zuffa needed a new way to get people to notice the UFC. The idea came to the Fertitta brothers when they were featured in the reality television series, American Casino. Seeing how well the series worked as a promotional vehicle for their casino holdings, and also how well the concept of reality television worked for the World Wrestling Federation (WWF) with their show, Tough Enough, which showed the progress of several wrestling "hopefuls" who lived and trained together in the hopes of acquiring a one million dollar contract to wrestle for the WWF, the UFC took the gamble on reality television, calling their series The Ultimate Fighter (TUF), which would feature up-and-coming Mixed Martial Arts (MMA) fighters living and training together, competing for a six-figure UFC contract. Fighters would be eliminated via exhibition fights (which would not be under the auspices of the state athletic competition, thus the results would not be revealed prior to the airing of the show).

The Ultimate Fighter was pitched to several networks, with each one rejecting the idea until Zuffa approached Spike TV (now The Paramount Network) with an offer to pay the ten million dollar production costs. Spike, eager for original programming, and also eager to see if they could share in the success that reality programming had for other channels and networks, picked up the show, and on January 17, 2005, Spike TV launched the first Ultimate Fighter in the timeslot following WWE's Raw. The show became an instant success for both Spike and the UFC, and in an unprecedented move, UFC President Dana White awarded an additional contract to runner-up Bonnar in their live fight at the finale of TUF 1. White credited the excitement and buzz of the fight between the two finalists (Stephan Bonnar and Forrest Griffin) for saving the UFC.

In May 2016, ESPN reported that Zuffa, LLC were in talks to the sell the UFC, although neither Zuffa nor the UFC commented on the report. However, on July 9, 2016, it was officially announced by Zuffa that the UFC would be sold to a group led by WME-IMG, its owner Silver Lake Partners, Kohlberg Kravis Roberts, and MSD Capital, for four billion dollars, marking the largest-ever acquisition in sports. Flash Entertainment will retain its minority stake, as will Dana White, who will remain UFC president, while Lorenzo Fertitta will step down as chairman and CEO.