Rule of Two

Darth Sidious and Darth Vader, the last known practitioners of the Rule of Two.

"Always two, there are; no more, no less. A master and an apprentice."

―Yoda^[src]

The Rule of Two was a Sith philosophy mandating that only two Sith could exist at any given time: a Dark Lord of the Sith to embody power, and an apprentice to crave it.^[1] The philosophy was created by Darth Bane,^[2] the sole survivor of a war against the Jedi Order a millennium before the Clone Wars. Recognizing that it was Sith greed and in-fighting that led to their destruction, Bane created the rule so the Sith could operate in secret, using subterfuge to plot their revenge against the Jedi.^[1]

The Sith carried out their vendetta for a thousand years, gaining power in secret while the Jedi had believed that the Sith were destroyed.^[3] The Sith finally revealed themselves during the Trade Federation's invasion of Naboo,^[4] after which they orchestrated the Clone Wars so Supreme Chancellor Sheev Palpatine—secretly the Dark Lord, Darth Sidious—could destroy the Jedi and transform the Galactic Republic into the Galactic Empire.^[5] The Sith ruled the galaxy for just over two decades, until they were destroyed by a redeemed Anakin Skywalker—who had been Darth Vader—who sacrificed himself to kill Palpatine during the Battle of Endor.^[6]