The Galactic Empire, also known as the First Galactic Empire, the New Order, or simply the Empire or the Order, and remembered as the Old Empire, was the galactic, autocratic government that replaced the Galactic Republic in the aftermath of the Clone Wars.
Rising to power in the final years of the Republic, the Sith Lord Darth Sidious gradually secured the government under his control through the persona of Sheev Palpatine, the last Supreme Chancellor of the Republic. Through his machinations as both Sidious and Palpatine, the Sith were restored to a position of dominance amidst the fall of the Jedi Order and the marginalization of the Galactic Senate. Without the Jedi guardians of peace and justice to oppose him, Sidious brought an end to a thousand years of democracy; in its place he installed the absolute rule of himself as Galactic Emperor.
For over two decades, opposition to the Imperial regime was ruthlessly suppressed by the rapidly developing Imperial Military that enforced Imperial expansion over the galaxy with the Empire further desiring to control over the universe and even time itself. Throughout most of the Empire’s existence, the Imperial Senate stood within the Empire as the last surviving symbol of the Republic. With the completion of the Death Star, the Emperor felt confident enough to dissolve the body of galactic representatives while maintaining his control over the galaxy through a collective of sector governors and the overall fear that the new battle station would inspire. However, the growing resentment to Imperial rule gradually led to the rise of various resistance movements that ultimately culminated in the formation of the Alliance to Restore the Republic. United by a common goal, the Alliance became a viable threat to the Empire after its successful theft of the Death Star plans and the station’s subsequent destruction at the Battle of Yavin.