Nurse Ratched in One Flew over the Cuckoo’s Nest.
Mr. Potter in It’s a Wonderful Life.
Annie Wilkes in Misery.
Villains don’t have to be political leaders to try and threaten all of existence. They don’t need to be on the level of Hitler nor Thanos. I think they need to know right from wrong and choose to do wrong using the little bit of power they have in the universe.
When I was five years old, the wicked witch of the west terrified me. I am not a superhero, nor a super spy, trying to save the world. I have nothing in common with those heroes, nor their villains. As an adult, neither Darth Vader, nor Sauron Scare me. I don’t really find them interesting either.
As for interesting authoritative villains, I basically have to go with my favorite actors. Gene Hackman as Little Bill in unforgiven. Joaquin Phoenix as emperor Commodus in gladiator. James Earl Jones as Thulsa doom in Conan the barbarian. Gary Oldman as zorg in the fifth element. Alan Rickman, as the sheriff of Nottingham in Robin Hood, and especially as Hans Gruber in die hard.
And let me give one more villain…
Hopelessness in Rocky. Apollo creed is not the villain. He is an obstacle for Rocky. But he’s just another fighter doing rock he does. The villain of the movie is despair, and sorrow, and the urge to quit. It sucks at Rocky. It gnaws on him. his fight with creed only shows us in physical terms, the emotional battle that he’s been going through his entire life.