Star Wars movies and TV shows. Star Wars books and video games, both canon and non-canon, have explored these stories in greater detail, but even then, the history has changed and had gaps over time.
It therefore feels like more than time for the Star Wars timeline to explore and reveal much more about the history of the Sith, especially on screen. Although subtle, the seeds of what that history could entail in the future have already been planted, although in some unexpected places. Specifically, Star Wars: The Acolyte Visual Guide, written by Pablo Hidalgo, has just reinforced a little-known Sith retcon, and it has major implications for the history of the Sith in Star Wars.
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Star Wars Confirms The Sith Were Originally "Conquerors"
The Idea Of Conquest Casts The Sith In A New Light
In both Star Wars canon and Legends, it's known that there was a Sith Empire. However, that Empire's history has long been shown as being contemporary with the Republic, with both sides engaged in a galactic war (that the Jedi also became involved in). Now, though, The Acolyte Visual Guide has suggested a much different history of the Sith and origin of the Republic. The text explains:
"After the defeat of Sith conquerors, the Republic emerges from the ashes of galactic conflict to reach unprecedented heights in the long strength of peace that follows."
There are several notable elements of this description of the Sith, although two of the most significant are the notion that the Sith were 'conquerors' and the timeline of the emergence of the Republic.
The description of the Sith as conquerors suggests that, at one point, the Sith had successfully conquered and ruled the galaxy—very different from the idea that the Sith and the Republic were locked in a battle. Stemming from that is the revelation that the Republic "emerges" from the defeat of the Sith, which means that the Republic and the Sith Empire weren't taking place simultaneously after all. This is a massive update to the history of the Sith, but it also builds upon a blink-and-you-miss-it retcon from a Darth Bane story.

Star Wars' Sith Empire Explained and Why Its Fall Was Inevitable
The Old Republic's Sith Empire is as fascinating as it was sinister, a major power before its inevitable fall in both Star Wars Legends and Canon.
This Latest Line Fits With A Surprising Darth Bane Retcon
The Idea Of Sith Conquerors Perfectly Complements Darth Bane's Star Wars Story
Darth Bane is well-known in Star Wars as the creator of the Sith Rule of Two, which dictates that there can only be one Sith master and one Sith apprentice at any given time. Bane created this rule because he feared the extinction of the Sith due to their history of in-fighting and only focusing on their own power rather than the larger preservation of the Sith. Again, though, the history of this rule, and of Bane's role in the galaxy, always seemed to be part of the Sith Empire that was acting in opposition to the Republic.
Now, though, based on this description in The Acolyte Visual Guide, it seems Bane's rule and the Sith Rule of Two may have predated the Republic entirely. This actually s a subtle Darth Bane retcon that rewrote the Sith history before. Namely, in the canon Star Wars comic Star Wars (2020) #20, written by Charles Soule, Elzar Mann, a Jedi from the High Republic Era, explains:
"This is what the Order was for me.... A golden age, about eight centuries after we ended the rule of Sith Lord Darth Bane."
This language, combined with the insight from The Acolyte Visual Guide, implies that it was Darth Bane who had ruled the galaxy, and the Jedi overthrew him, bringing about the emergence of the Republic.
It's Time For Star Wars To Give Us The History Of The Sith
We Need To Know More (And The Acolyte Wasn't Enough)
This is a fascinating new perspective on the history of the Sith, and it only makes me all the more eager for Star Wars to explore this history in-depth on screen. Initially, The Acolyte was billed as a story not of the Jedi but of the Sith, and while that proved true in certain ways (such as with Qimir/the Stranger), the show didn't really offer that much more in the way of the Sith's extensive history. Even the sighting of Darth Plagueis, while thrilling, was brief and unexplored.
It's therefore absolutely time for Star Wars to put a true Sith story at the forefront in a show or movie.
It's therefore absolutely time for Star Wars to put a true Sith story at the forefront in a show or movie. The Sith history has long been complicated and a bit confusing, and a streamlined, on-screen story about this history would be as clarifying as it would be exciting. This update on a previous retcon of the Sith history in Star Wars only makes it all the clearer that we need such a story.