Throughout the Star Wars saga, audiences have learned that there must always be a balance between the forces of good and forces of evil, with the Jedi always fighting back the Sith and their nefarious ways. In the book Star Wars: The Last Jedi: The Visual Dictionary, information about Snoke confirms that the galaxy hasn't seen a true Sith Lord since the death of Darth Vader. "Snoke is powerful in the dark side of the Force, but he is not Sith," the book clarifies.