One of the things that we know about the Sith is that there’s always a master and an apprentice. While Palpatine was almost always the master in his history in Star Wars, he was once the apprentice to Darth Plagueis the Wise. However, similar to how the Sith Lords of the past operated, Palpatine presumably killed his own master in his sleep. So, when and why did Palpatine kill Darth Plagueis?
Palpatine presumably killed Darth Plagueis sometime during his rise to power as a senator. However, in the Legends storyline, he killed his master just before he was elected Supreme Chancellor. And he killed Plagueis because he didn’t have any use for him anymore and was not about to share power with him.
Throughout the entire storyline of Star Wars, Palpatine was always hungry for power, and that is why he always tried to find a way wherein he ended up on top of everything that he did. As such, his ambition and hunger for power drove him to kill Darth Plagueis. That said, let’s look at when and why Palpatine killed his own master.
When Did Palpatine Kill Darth Plagueis?
The Sith Order operated in secret for hundreds of years in secret due to the Rule of Two, which mandated that there should only be two Sith Lords at a time: a master and an apprentice. Of course, throughout that time, it became customary for the apprentice to kill the master to take their place. And if the apprentice failed to kill the master, the master would kill them and look for a new apprentice.
For hundreds of years after Darth Bane created the Rule of Two, the Sith operated this way and survived without arousing the suspicion of the Jedi Order. Of course, this continued until Darth Sidious’ time as he also practiced the Rule of Two. And like all of the Sith Lords that came before him, there was a time when Palpatine was just an apprentice.
Palpatine’s master was Darth Plagueis the Wise, a scholar in the dark side of the Force and said to be so powerful that he could influence the midi-chlorians to create life. During the events of Star Wars Episode III: Revenge of the Sith, Palpatine told the Tragedy of Darth Plagueis the Wise to Anakin Skywalker to tempt him to turn to the dark side of the Force. Palpatine seemingly told Anakin that he was responsible for killing Plagueis while the master was asleep. But when did this happen?
In the Legends storyline of Star Wars, it was told that Palpatine killed Darth Plagueis during the events of Star Wars Episode I: The Phantom Menace. Remember that Queen Amidala asked the Senate to replace Chancellor Valorum due to his inability to control the bureaucrats of the Senate. As such, a new Supreme Chancellor had to be elected, and it just so happened that Palpatine was one of the nominees for the position.
While Qui-Gon Jinn and Obi-Wan Kenobi fought the Trade Federation at Naboo, Palpatine was elected the new Supreme Chancellor. He celebrated his impending victory with Darth Plagueis, only for him to kill his master in his sleep after the celebration. But the problem with this storyline was that three Sith Lords existed then: Plagueis, Sidious, and Maul.
This story wasn’t carried over in the canon storyline of Star Wars. Of course, Palpatine still killed his master, but it was never mentioned when he did so. But the Star Wars: Secret of the Sith novel, a canon book in Star Wars, told Palpatine’s rise to power from his perspective. An excerpt in that book reads:
After centuries in the shadows, the Sith were poised to emerge once more. As a dark apprentice, I sensed that the Galactic Republic was in disarray. Its delegates held no interest in the common good. They would be easy targets for my influence. Serving as a senator, I manipulated their greed in my favor. With each new act of legislation, I rose through their ranks. Total control of the galaxy’s governing body drew ever closer. But ascension in the Senate would not be enough. My master, Darth Plagueis, had served his purpose. I struck him down, claiming his place as the one true master of the Sith.
As you can see in that excerpt, Palpatine said that he killed his master when he was rising in power as a senator. However, instead of killing him just before he became Supreme Chancellor, he killed him somewhere when he was rising in power within the Senate. As such, he became the new master of the Sith right after killing Plagueis, meaning he could now take an apprentice in the form of Darth Maul. Unlike the Legends storyline, there were never three Sith Lords at a time because Palpatine killed his master when he was still a senator and probably right before he took Maul in as his apprentice.
Why Did Palpatine Kill Darth Plagueis?
Of course, a lot of fans weren’t surprised about the fact that it was Darth Sidious that killed his own master, as this was the way that the Sith operated. The Sith were so hungry for power that it was normal for one Sith Lord to betray another. And that was why the Rule of Two was created to minimize infighting among the Sith.
Still, the Sith fought one another as it was customary for the apprentice to kill the master to take their place. But this allowed the Sith to continue operating with the tradition of a master training an apprentice to become stronger than them so that they could one day take their place and follow this tradition. And that means that Palpatine killed Darth Plagueis because he wanted to be the new Sith master.
As mentioned in the above-quoted excerpt, Palpatine no longer had any use for Plagueis because he had already ascended to the Senate with the help of his master. Plagueis helped groom Palpatine to become a senator, and when Darth Sidious had already taken a seat in the Senate, his master was no longer of any use to him. Of course, he also wanted to be the master that didn’t serve as a thrall to anyone, and he achieved the position of Supreme Chancellor through his own machinations and deceptions.
In a way, Palpatine’s hunger for power drove him to kill his master because he didn’t want to share his power with Plagueis. He was only using his master to get his position as a senator. And when he already got what he wanted, he no longer wanted to share the spoils of glory and victory with his master.
Of course, the fact that Palpatine had to kill Plagueis was integral to his future plans because he needed to be the emperor that ruled everything. Had Plagueis been alive during the rise of the Empire, Palpatine would only serve as a puppet to his master. Of course, with Plagueis around, Palpatine wouldn’t have been able to take on an apprentice. And we all know how important it was for him to take Dooku and, eventually, Anakin as his apprentices.