Sheev Palpatine

Behind the Scenes
Palpatine's first name was revealed to be Sheev in James Luceno's novel Tarkin in 2014; The name was originally conceived by George Lucas for a reveal in his cancelled live-action TV show Star Wars: Underworld which was in development hell for years prior to being cancelled, which would theoretically make his first name G-canon.

Appearances & Mentions

 * Darth Plagueis
 * Star Wars: Episode I - The Phantom Menace (First Referred to as Darth Sidious)
 * Star Wars: Episode II - Attack of the Clones
 * Star Wars: Clone Wars - "Chapter 21" (Mentioned Only)
 * Hero of Cartao
 * The Cestus Deception
 * Star Wars: The Clone Wars (Film)
 * Star Wars: Episode III - Revenge of the Sith
 * Star Wars: Episode IV - A New Hope (Mentioned Only)
 * Star Wars: Episode V - The Empire Strikes Back (First Appearance; Hologram Only)
 * Star Wars: Episode VI - Return of the Jedi (Appearance of First Death)
 * Dark Empire 1: The Destiny of a Jedi (Mentioned Only)

Non-Canonical Appearances & Mentions

 * Star Wars Infinities: A New Hope
 * Star Wars Infinities: The Empire Strikes Back
 * Star Wars Infinities: Return of the Jedi