We Should Thank (Or Blame) George Lucas For Palpatine's Resurrection
Emperor Palpatine's return from the dead in Star Wars: Episode IX – The Rise of Skywalker did not help to salvage the movie and the sequel trilogy, as it was clearly intended to. Few people liked it, many mocked it, most saw it as a cheap attempt at nostalgia baiting.
But Episode IX was not Palpatine's first resurrection. The key part of the Sith quest for absolute power has always been conquering death, and Palpatine was the one who succeeded, with certain limitations.
After the events of Return of the Jedi, his spirit leaped into a clone body, and he hid himself away on a planet strong in the dark side while he developed a fleet of superweapons with which to retake the galaxy.
Sounds like the setup of Episode IX? Actually, this also describes the premise of Dark Empire, a comic miniseries by Tom Veitch and Cam Kennedy published in the early '90s. This was one of the most important stories in the old Star Wars Expanded Universe. Along with the rest of EU, it got branded non-canon (or "Legends") after Disney acquired Lucasfilm in 2012.
And the core idea of the premise originated with George Lucas himself. As Veitch explained in an interview back in 2016, he originally proposed introducing a new character who had donned Darth Vader's iconic armor and mask.
"George vetoed that idea (although he did allow us to have Vader appear in dreams and memories). He said, no, you can't bring back the Vader costume... but if you can figure out how to bring back the Emperor, that's o.k. The obvious way to bring back the Emperor was with cloning, which George immediately approved."
And Lucas, by all accounts, really liked and enjoyed the resulting story. Notably, even back then he seemed to be in the minority. Dark Empire was not exactly hated by the fandom, though neither was it much loved… but most of EU writers, especially novel writers, quietly ignored it, and tried to reference it as little as possible.
And Dark Empire at least had the advantage of making the fact of Palpatine's return as a clone – and, accordingly the search for a way to prevent him from returning ever again – the axis of its plot.
So it is not really clear what Disney was thinking when they gave a green light to resurrecting the Emperor as a last-minute, zero-foreshadowing addition to the final movie of the sequel trilogy, with a sloppy, almost nonexistent in-story explanation.
"Somehow, the Emperor returned" became a meme used to point at bad writing thanks to that!