Gunther

Hahn met English professional wrestler Jinny Sandhu while competing on the European independent circuit, and the two began dating while working together on WWE's NXT UK brand. They married in a private ceremony in 2022, followed by an additional wedding ceremony held in London in April 2023. The couple welcomed a son on 27 December 2023 and purchased a home in Cambridge in 2025.

During his youth in Vienna, Hahn played association football as a goalkeeper before stopping at age 15 to focus on professional wrestling. He is an avid supporter of Austrian club SK Rapid Wien as well as German side FC Schalke 04. While he studied English in school as a child, he became fully fluent around 2012 by communicating regularly with international wrestlers on the European circuit.

Hahn began his formal wrestling training at Wrestling School Austria under Michael Kovac, making his professional in-ring debut in November 2005 under the ring name Big Van Walter. In December 2006, he traveled to Japan to train at the Pro Wrestling ZERO1-MAX dojo alongside heavyweight trainers Riki Choshu, Tatsuhito Takaiwa, and Tomohiro Ishii. During this Japanese tour, he competed under a masked persona named Gha-cha-ping before returning to the Big Van Walter moniker.

He established himself as a prominent figure in Germany's Westside Xtreme Wrestling (wXw), becoming the youngest winner of the 16 Carat Gold tournament in 2010 at age 22. In addition to winning three wXw Unified World Wrestling Championships and four World Tag Team Championships, Hahn served as the head trainer of the wXw Wrestling Academy from 2015 to 2020. In 2016, he co-founded the Ringkampf stable alongside Axel Dieter Jr., Axel Tischer, and Christian Michael Jakobi, adopting the motto "Die Matte Ist Heilig" (The Mat is Sacred).

Beyond Germany, Hahn competed extensively across the international independent scene. Between 2017 and 2019, he captured several major titles, including the PWG World Championship in the United States, the OTT Championship in Ireland, and both the World and Atlas Championships in the British promotion Progress Wrestling.

Hahn signed with WWE in late 2018 and was assigned to the NXT UK brand, making his debut in January 2019 at NXT UK TakeOver: Blackpool by confronting WWE United Kingdom Champion Pete Dunne. At NXT TakeOver: New York in April 2019, he defeated Dunne to win the championship. Shortly after, he reunited with former Ringkampf stablemates Marcel Barthel, Fabian Aichner, and Alexander Wolfe to form Imperium.

Hahn held the NXT United Kingdom Championship for 870 days, surpassing Dunne's previous record to become the longest-reigning champion in the title's history. His reign included successful defenses against Tyler Bate, Tommaso Ciampa, and Ilja Dragunov. Dragunov ultimately ended Hahn's 870-day reign in a rematch at NXT TakeOver 36 in August 2021.

In early 2022, Hahn moved to the American NXT brand. Following a victory over Roderick Strong in January 2022, his ring name was officially changed to Gunther. Around this period, he altered his training regimen and diet, shedding roughly 65 pounds to transition from over 300 pounds down to 250 pounds.

Gunther made his WWE main roster debut on SmackDown in April 2022, accompanied by Ludwig Kaiser. Two months later, he defeated Ricochet to capture the WWE Intercontinental Championship, becoming the first Austrian wrestler to hold the title. He reformed Imperium on the main roster by reintroducing Giovanni Vinci alongside Kaiser.

During his title reign, Gunther mounted successful defenses against challengers such as Shinsuke Nakamura, Rey Mysterio, Sheamus, Drew McIntyre, and Chad Gable. In September 2023, he surpassed The Honky Tonk Man's 454-day mark to become the longest single-reigning Intercontinental Champion in WWE history. In February 2024, he also broke Pedro Morales' record for the most cumulative days as champion across all reigns. His reign reached 666 days before ending in a defeat against Sami Zayn at WrestleMania XL in April 2024.

In May 2024, Gunther won the King of the Ring tournament by defeating Randy Orton in the final, securing a world title match at SummerSlam. At SummerSlam 2024, he defeated Damian Priest to capture the World Heavyweight Championship, marking his first world title in WWE. He made successful defenses against Orton, Zayn, Priest, and Finn Bálor before losing the championship to Jey Uso at WrestleMania 41 after a 259-day reign.

Gunther reclaimed the World Heavyweight Championship by defeating Uso in June 2025. During this era of his career, he became known as the "Career Killer" after defeating multiple prominent veterans in their retirement bouts, including Goldberg at Saturday Night's Main Event XL, John Cena at Saturday Night's Main Event XLII, and AJ Styles at the 2026 Royal Rumble.