In the late 1940s, L. Ron Hubbard (1911 - 1986) was a moderately successful author of science fiction and fantasy tales appearing in the pulp magazines of the day. But Hubbard could see that the pulp era was ending; most pulps were ceasing publication, while a very few titles survived by reformatting as digest-sized magazines. By 1950, the media were being swamped with pseudoscientific nonsense, in what in retrospect was the first giant wave of pop pseudoscience... particularly, the media were full of flying saucer (UFO) accounts, and breathless reports of scientific validation of "Extra-Sensory Perception" (reading minds, foreseeing the future, being able to perceive distant or hidden objects, etc.). Hubbard chose to join the bandwagon, but what he came up with was Dianetics, a sort of primitive parody of psychoanalysis. The analyst was called an "auditor," and what he looked for in the patients was "engrams," very traumatic experiences whose memories were suppressed, and causing all kinds of problems. In other words, it was a disguised self-help scam. Once you had remembered and processed your engrams, having paid your official Hubbard-trained auditor for how many sessions it took, those engrams could no longer bother you, because you became "clear" of those hidden bad memories, and any resulting behavioral and emotional problems that had been caused by them thus magically vanished. Appropriately, the first article presenting the miraculous promise of Dianetics was published in a May 1950 issue of a popular science fiction magazine. His followup book was a flop, and he had to declare bankruptcy, losing the rights to his own book.  Then a fellow author pointed out to Hubbard that the money he should have been making from Dianetics was taxable... if he could reconfigure the scam as a religion, the profits would be tax-free! Hubbard then created Scientology, which used all the apparatus of Dianetics, but also proclaimed the truth of a wild science-fictional religion invented by Hubbard, and pointedly incorporated many of the currently promoted fads of pseudoscience.  The believer's main goal now was to become "completely clear," after long and expensive auditing and training sessions... and such a Clear would have god-like powers... ultimately becoming something called an "operating Thetan," with total mental control over "all forms of matter and energy."

Scientology seemed to be the right thing at the right time, and it grew explosively, making Hubbard fabulously wealthy. But the cult increasingly transformed into a destructive cult, causing great physical and mental harm of some of its members, especially in the so-called Sea Org branch, which resulted in a number of nations declaring the cult to be "undesirable." Hubbard became convinced that the FBI was out to get him, and for the latter part of his life he sometimes lived at sea, in international waters, or even out of a trailer,  which he moved constantly about the US. His paranoia led to the infamous "Operation Snow White," in which members of the Church were asked to get jobs at various law enforcement agencies, locate all files the agencies kept on Scientology, and destroy them!  At one point Hubbard decided to resume writing science fiction novels, which  became instant best sellers since cult members were all required to buy them, since they had to buy anything published by Hubbard on any topic. Eventually one of his nearly-unreadable novels was adapted as a movie, with the Church and one of the movie's stars paying production costs.  Scientology has always used extensive advertising, and has many famous "converts" to show for it, such as Tom Cruise. Today it remains a superficially thriving cult which mercilessly milks its converts for their last dime.  The current leader of the Church grew up in the cult, and is only in his 60s today, but it seems clear that to grow significantly after 73 years, the Church desperately needs some new ideas and gimmicks.

The number of members the Church of Scientology has worldwide has always been a closely guarded secret. Over the years, enough members have left the cult and revealed its teachings, from lowest to highest level, that a pretty good idea can be formed of most of them. One big emphasis is on reincarnation... with enough expensive courses and training under your belt, you can remember your "first trillion years" of existence! Historically, many religions have operated as mystery cults. That is, the true teachings of the cult are withheld from members until they reach a highly advanced rank within the cult... then the ultimate, top-seccret teachings are revealed bit by bit. Scientology has a number of these ultimate secrets, which have been revealed by high-ranking cult defectors. Typical ultra-top secret: Hubbard was actually God in disguise.  Both journalists and academics have, over the years,  been decisively discouraged from investigating the Church.

A number of former (and even current) cult members have gone on to found their own cults, which reuse some aspects of Scientology, blended with other religious themes and somewhat different self-help gimmicks.

When Scientology was being invented, the two overwhelmingly most popular pseudosciences involved UFOs (flying saucers and their occupants), and mystical mental powers (ESP)--- so Hubbard worked both of these into his cult, but only members who had paid immense sums of money to the cult got to be exposed to the "true" role of aliens in earth's history, and the "true" way to achieve godlike powers!  Secret knowledge which only the most advanced Scientologists could hope to deal with--- lesser beings would be driven insane by the implications!