While not truly Sith, the Inquisitors wore their colors and used red-bladed lightsabers, weapons typically only used by Sith Lords and masters of the Knights of Ren.
In contrast to their counterparts, the Sith Warriors, Inquisitors specialized in Force abilities as opposed to martial might, and many would devote much time to researching new skills to survive in the cutthroat Sith political environment. Few acolytes succeeded in becoming Inquisitors.
While they may have been brutally trained by Darth Vader himself and allied with Palpatine, they are not truly Sith as the Rule of Two's roles of master and apprentice were already filled by the two.
Fearing the threat that the surviving Jedi posed to his rule, Darth Sidious created the Inquisitorius to track down and corrupt or eliminate the last remaining Jedi. Sidious then tasked his Sith apprentice, Darth Vader, with training the former Jedi in the dark side to become Inquisitors in their service.
Rule of Two: There can only be two Sith, a Master and their Apprentice. (This was was to stay under the jedi radar, and leads to all the betrayal, murder and secret apprenticices you would expect). Inquisitorius: Force sensitives that use the dark side of the force.
The Difference Between Sith and Inquisitors - Star Wars Explained
Are the Inquisitors actual Sith?
Though the Inquisitor came into the service of the Empire and the Sith, he was not a Sith himself. When the Inquisitor entered the Jedi Temple's Archives, he was confronted by the Sith Lord Darth Vader, who was once Anakin Skywalker before his own fall to the dark side.
Reva took a lightsaber blade to the middle twice and survived. Writing aside, she has far more determination and will to live than any of the Inquisitors I just mentioned. And she's still weaker than any named Jedi or Sith.
The Inquisitors' power in the Force varies by the individual. While the Grand Inquisitor is the strongest of the group, others, like the Tenth Brother, are considerably weaker. Vader and Sidious deliberately didn't teach the Inquisitors the true ways of the Sith, as their servants may then have truly become threats.
Reporting directly to the Emperor or the Supreme Commander, they were officially classified as part of Imperial Intelligence however, still outranked a bulk of the Galactic Empire's ranks. For a time, they were made subservient to Ferus Olin.
For example, the main films had Darth Maul, Count Dooku, Darth Sidious, and Darth Vader as the only Sith Lords, but Maul was no longer a Sith when Sidious took Count Dooku as his apprentice, and despite ruling the First Order, neither Snoke nor Kylo Ren were Sith either.
Star Wars has finally revealed how Palpatine turned Jedi into Inquisitors. Darth Vader and his Inquisitors were a terrifying force in the Dark Times of the Empire's reign, hunting the few Jedi who survived Order 66. They were also a symbol of Palpatine's malevolence, because every one of them was a former Jedi.
Consisting often of former Jedi, the Inquisitors were initially weak in the usage of the dark side of the Force and utilized the defensive fighting discipline common to most of the Jedi Order - which emphasized maintaining a strong defense and only moving to attack when there was no other recourse available.
Inquisitors weren't nearly as powerful as Sith, so they relied on intimidation to aid them in combat, with their spinning lightsabers assisting them with weaponizing fear. While the spinning double-bladed lightsabers weren't effective against emboldened enemies, they did provide some practical benefits.
The title was earned after an Inquisitor proved their worth to the Inquisitorius. The title did not refer to blood relation, but instead fostered a sense of unity amongst the Inquisitors.
For a Jedi hunter like the Inquisitor, this function likely served as a way to intimidate, or frighten opponents, as well as deflect any form of direct attack.
The first grand inquisitor in Spain was the Dominican Tomás de Torquemada; his name became synonymous with the brutality and fanaticism associated with the Inquisition.
As Palpatine's Sith apprentice, Vader was in charge of the Inquisitors, who quickly came to fear his power. While Vader was far more powerful than the Inquisitors, he was not nearly as sadistic as they were, as shown by their hunting methods and what they did with the Jedi they captured.
In addition to being the Inquisitorius' headquarters, Fortress Inquisitorius was also where Jedi were taken to be corrupted by the dark side and formed into Inquisitors. If the torture tactics to corrupt them were not successful, they were killed.
Storywise, the majority of the Inquisitors died before the events of the original trilogy, with the final Inquisitors dying at the hands of the Ghost team in Rebels. The Grand Inquisitor died at the end of the first season of Rebels during a duel with Kanan Jarrus, and never received a replacement.
In official canon, the Sith were an order of dark side Force users who used their abilities for personal gain. Canonically, the Sith who were not former Jedi include: Darth Sidious. Darth Plagueis.
They are the antithesis and ancient enemies of the Jedi. The Sith Order is depicted as an ancient cult of warriors who draw strength from the dark side of the Force and use it to seize power by any means necessary, including terrorism and mass murder; their ultimate goals are to destroy the Jedi and rule the galaxy.
After the deaths of Grand Inquisitors Malorum and Hydra some time around circa 18 BBY, Torbin took over as the leader of the Inquisitorius, assuming the prefix, "Lord." As the Grand Inquisitor, he only answered to the Emperor, Dark Lord of the Sith Darth Vader, and the upper echelons of the Empire; he also commanded ...
Most notably, all would wield Sith-style lightsabers; though most were simply their original lightsabers with their Ilum crystals replaced with synth-crystals.
