Dooku

Dooku was born to the ruler of the planet Serenno, but he was rejected by his father for being force sensative and was instead accepted into the Jedi Order. After leaving the Jedi Order, Dooku went back to his home planet and reclaimed his title as "Count Dooku" by conquering his brother. Dooku was then approached by Darth Sidious who not only recruited Dooku into the Sith Order but also to be the leader of the Separtist movement.