Roman Reigns is the longest-reigning world champion of the modern era WWE who has now surpassed the 600-day landmark.
The Tribal Chief returned from a hiatus in the summer of 2020, Summerslam to be precise. A week later on August 30, 2020, at the WWE Payback premium live event, Roman Reigns defeated Braun Strowman and The Fiend Bray Wyatt in a Triple Threat Match to win the Universal Championship. He’s been holding that belt ever since.
During his current reign, he’s overcome all the top talents that Smackdown has to offer including a Raw superstar in Seth Rollins along with legends like WWE Hall of Famers Goldberg or Edge.
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In the main event of WrestleMania 38 Night Two, Roman Reigns defeated Brock Lesnar to win the WWE Championship in the Biggest Wrestlemania Match of All Time. Thus, he became the Undisputed WWE Universal Champion. (It appears that the two titles will remain separate and will be defended, separately in the future)
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Roman Reigns longest-reigning champion of modern era
As the dual run continues, Roman Reigns has now been the Universal Champion for 600 days. He is also the longest-reigning World Champion of the last 35 years. Only four other men in WWF/E history had a single World Title reign longer than The Head of the Table’s current reign. But all those reigns took place in the old school era where competition used to be pretty less for top superstars. Below is that list:
1. Bruno Sammartino (two different title reigns – 2,803 and 1,237 days)
2. Bob Backlund (2,135 days)
3. Hulk Hogan (1,474 days)
4. Pedro Morales (1,027 days)

In more update, Roman Reigns hasn’t been pinned in 871 days. His last pinfall loss took place at the TLC 2019 pay-per-view to Baron Corbin. As per the recent updates, this strong status won’t change anytime, soon. There are speculations about the title reign possibly being intact until the much-anticipated program with The Rock begins in time for Wrestlemania 39. (info courtesy WWFOldSchool)
Following Wrestlemania 38, Roman Reigns was rumored to defend his title at Wrestlemania Backlash 2022 against Shinsuke Nakamura. But the storyline was dropped even after Reigns and The Usos downed the King of Strong Styles. Now, the top babyface superstar Drew McIntyre is the next in line for the Universal Title.