Emperor Palpatine was the ultimate evil of the Star Wars galaxy. He was once a Senator and then Supreme Chancellor of the Galactic Senate. However, all this was merely an act, for Palpatine was really Darth Sidious. Though some would argue Palpatine disguised himself as Darth Sidious, the motives of Darth Sidious were merely acted out under the guise of Palpatine. In any case Palpatine and Sidious are one in the same. Emperor Palpatine was the main antagonist to the Rebel cause during Episodes IV-VI. He was a powerful Sith Master which aided him in his quest for power. Palpatine would eventually control almost all of the galaxy and there were hardly any systems without the Empire's presence. After taking over the Senate and forming the Galactic Empire, Palpatine, along with his apprentice Darth Vader, exterminated all the Jedi Knights to prevent any opposition, at least so they thought. A small Rebellion formed and eventually grew. With the help of Vader's own son, Luke Skywalker, the Rebellion became a force to be reckoned with. For this reason, and the fact that Luke has begun training as a Jedi thus proving a threat to Palpatine, the Emperor took interest in trying to turn Luke to the Dark Side. However, Luke defeated his father, Darth Vader, in a vicious lightsaber duel aboard the second Death Star, proving that he was a true Jedi Knight. Palpatine grew furious that he had failed to turn Luke to the Dark Side and used the Force lightning techinque to attempt to kill him. However, Darth Vader intervened, saving his son and killing Palpatine all in a split-second. And so it was that the greastest menace the Star Wars galaxy ever saw was vanquished.