He, along with his apprentice Count Dooku, are the ones who stir up the tensions in the Outer Rim territories and he supplies them with a droid army to fight the Clone Army of the Republic, which Palpatine was also responsible for.
So, it would appear that Palpatine was actually responsible for creating his own Rebellion, which is, of course, ultimately successful and destroys him. Well done.
Of course, if you remember all the political details of the Star Wars prequels, though, you’d be forgiven for losing consciousness at the mere mention, you’ll remember that pretty much all of it was just one big plot by Darth Sidious/Emperor Palpatine to take over and create the Galactic Empire.