The Galactic Empire is one of the main factions in the fictional universe of Star Wars. It is a galaxy-spanning regime established by the series' lead villain, Palpatine, to replace the Galactic Republic in Star Wars Episode III: Revenge of the Sith. The Galactic Empire is introduced in Star Wars Episode IV: A New Hope. The Empire also appears in Star Wars Episode V: The Empire Strikes Back, and in Star Wars Episode VI: Return of the Jedi.
The Empire's origins are explained in Star Wars Episode III: Revenge of the Sith, where it replaces the Galactic Republic in the midst of a galactic civil war orchestrated by Palpatine, then the Republic's Supreme Chancellor. In a scene towards the end of the film, Palpatine appoints himself Emperor in the presence of the Galactic Senate, afterward the Imperial Senate. By the time of A New Hope, the Empire has transformed into a fully totalitarian regime, with opposition in the form of the Rebel Alliance.
The Galactic Empire is described in various Star Wars media as a brutal dictatorship, one based on "tyranny, hatred of nonhumans, brutal and lethal force, and, above all else, constant fear."
When do you think people die? When they are shot through the heart by the bullet of a pistol? No. When they are ravaged by an incurable disease? No. When they drink a soup made from a poisonous mushroom!? No! It’s when… they are forgotten.