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human
[Star Wars Legends] How were Darth Sidious/Palpatine and Darth Vader remembered?

Both on short term (years to decades) and long term (centuries)

I know all this is probably Legends, but i wondering how the memory of Darth Sidious lived on in the EU. 

How was Emperor Palpatine remembered in the New Republic? Was he, after hundred of years, remembered as an evil dictator like people nowadays remember Hitler? Or was the opinion of the further generations more nuanced? Did the fact that he was a Sith Lord ever became general knowledge through the Galaxy? 

And how was Darth Sidious remembered by the New Sith Order or all other Dark Side Users years or centuries after his death? Was he respected for almost destroying the Jedi? Or was his Galactic Empire seen as an failure? 



Bonus question: Same questions as above, but now about Darth Vader? Did the public ever hear the truth about his redemption? Did children at schools learn about him as an hero or a bad guy?
gpt
For Sidious, the answer is "it's complicated".

The average citizen of the New Republic obviously saw him as little more than a warmongering, power-seeking tyrant; especially in later years, as Luke and the New Jedi Order revealed his full attachment to the Sith cause (and the implications for the reality behind the Clone Wars). Frankly, they'd have had little trouble propogating this particular viewpoint: Palpatine's policies as Emperor tended towards the most extreme and oppressive and his own writings revealed the depth of his manipulations as a Sith Lord. 

A significant fraction of the Imperial Remnant initially viewed him as a fallen hero, slain by vicious terrorists (and later, the traitorous Darth Vader). As time passed, however, the Imperial Remnant began to shift it's views. I'd say this was largely because the surviving Imperial leaders tended to be the more rational and peaceful of the Empire's former hierarchy, the aggressive and spiteful ones having been wiped out either by infighting or fruitless one-by-one individual fights with the New Republic. Not only was this new crop of more sensible Imperial leaders more prone to recognizing the oppressiveness of Palpatine's policies, they also tended to have met him in person - and many of those who did recognized a lust for power and near-madness in the man that made them uncomfortable.

The Sith were badly destroyed during this period as well, but those who did remain in the decades after the New Republic's rise tended to have mixed-to-dim opinions of Palpatine - often taking the view that while he was a genius of Sith manipulation and power control, he was also critically flawed in that he allowed himself to be consumed by his own maddened lust for power. Other minor Sith splinter groups were often suppressed or hunted by Sidious, giving them negative opinions of him.


Darth Vader is a much easier answer: Nobody liked the guy. The New Republic opted to heavily differentiate between Anakin Skywalker and Darth Vader, portraying Anakin as a victim of Dark Side control by Sidious to absolve him of actions taken while under the Vader persona while highlighting Anakin's final redemption and role in balancing the Force. In the Imperial Remnant, opinion was perhaps even poorer: Vader was already known among the Imperial staff as a temperamental, anger-prone, and dangerous individual who it was risky to be around. While he was briefly portrayed a victim killed by Rebellion terrorists, as it became clear that Vader had in fact turned on the Emperor his name was lowered to the point it was used to mean traitor.