Imperium is a European villainous professional wrestling tag team consisting of leader Gunther of Austria and Ludwig Kaiser of Germany.

Previously working for several European promotions, including together as part of the stable Ringkampf, Gunther and Ludwig Kaiser, then known as Walter and Marcel Barthel, respectively, signed with the WWE in 2019, having been assigned to the NXT UK brand and were paired with Giovanni Vinci, then known as Fabian Aichner, of Italy, and Alexander Wolfe of Germany; the stable started to use the name Imperium, with the motto of "The mat is sacred" (German: Die Matte ist heilig) imported from Ringkampf.

From 2016 to 2019, Gunther and Ludwig Kaiser (then known as Walter and Axel Dieter Jr.) were members of a stable called Ringkampf alongside Timothy Thatcher and Christian Michael Jakobi, in which they worked on several European promotions.

At Chapter 47, Ringkampf (Walter, Dieter and Thatcher) challenged British Strong Style (Pete Dunne, Trent Seven and Tyler Bate) for all of their championships, in a six-man tag team match, but they were unsuccessful.

[4] On the 22 May 2019 episode of NXT UK, Walter won a rematch for the United Kingdom Championship against Dunne, after interference by the European Union (Fabian Aichner and Marcel Barthel), thus establishing himself as a heel.

[15][16] At NXT TakeOver 36, Walter dropped the United Kingdom Championship to Dragunov in a rematch ending his historic reign at 870 days.

[18] They later lost the titles back to MSK at Stand & Deliver the following year, in a triple threat match that also involved The Creed Brothers.

[21] Prior to Gunther's title defense at Clash at the Castle, Kaiser announced the reformation of Imperium by reintroducing Aichner, now known as Giovanni Vinci.

At Extreme Rules on 8 October Imperium lost to The Brawling Brutes in a Six Man Tag Team Good Old Fashioned Donnybrook match.