Sith Juggernauts existed as Sith Warriors fighting for the Sith Empire during both the Great Galactic War and the subsequent Cold War, around the year 3653 BBY. These Sith were experts in enduring combat situations, and they were recognized for utilizing armor that granted them unique defensive capabilities during battles. In battle, Sith Juggernauts typically used a single lightsaber, and they often demonstrated proficiency in using the Force to induce terror and despair among their adversaries. A common trait of Sith Juggernauts was a highly developed muscular physique, which provided a physical advantage when wielding a lightsaber or engaging in combat.
Within the Star Wars: The Old Republic MMORPG, the Sith Juggernaut serves as an advanced class option for the Sith Warrior class. This specialized class emphasizes the use of robust armor and enhanced resilience during combat encounters. The equivalent archetype within the Republic ranks is the Jedi Guardian. It would seem that the Sith Juggernaut takes inspiration from Darth Vader, considering the immense strength, protective armor, use of a single lightsaber, and commanding Force abilities. However, the official source of inspiration for the juggernaut is Marka Ragnos.