6. Emperor Sheev Palpatine (A.K.A. Darth Sidious)
You won’t hear anyone calling this character Sheev, even though it’s his actual first name. He’s Darth Sidious, and he’s too frightening for people to defy him and call him anything else. Even Darth Vader takes orders from him, albeit reluctantly at times. He’s gone by a handful of titles over the years. He started out as Senator Palpatine, and from there became Supreme Chancellor before becoming Emperor. Darth Sidious is his Sith name that he largely kept hidden from the public.
In the prequel trilogy and The Clone Wars, we see quite a bit of Palpatine as a Senator. He can appear very agreeable, but he always has an angle on everything. He knows that being inside the government gives him an upper hand, and he uses that to rise to complete power.
Many feared Darth Vader, but Vader never had Palpatine’s reach. He’s a crucial player in this story. Without him, the galaxy is a safer but vastly more boring place.