Not dead. The plot of the rise of the rebels took place between Star Wars 3 and 4 (that is, the story of Star Wars prequel 3 to 1). At this time, Anakin Skywalker degenerated from a Jedi to the Sith Lord Darth Vader, and obeyed the orders of the imperial emperor and his men, almost destroying all the Jedi.

In Star Wars 6, Darth Vader (Anakin Skywalker) held the imperial emperor above his head and threw him into the reactor pit of the Death Star in order to save his son luke skywalker. However, Darth Vader was struck by the emperor's powerful force lightning, seriously injured and his life-sustaining armor was destroyed. After saving his son and reborn his soul in the bright side of the Force, Anakin died peacefully and became a part of the Force.