Scientology founder L. Ron Hubbard based his religion on a belief in extra-terrestrials...

"At these higher levels ... Scientologists learn Hubbard's secret theory of human suffering,
which he traces to a galactic battle waged 75 million years ago by an evil tyrant named Xenu."

From an L.A. Times article about Tom Cruise and Scientology:
http://www.latimes.com/business/la-fi-scientology18dec18,0,2963052.story?coll=la-home-headlines

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