Abbé Augustin Barruél (February 10, 1741 - May 10, 1820) was a Jesuit priest mostly known for originally inventing the conspiracy theory involving the Knights Templar, the Bavarian Illuminati and the Jacobins in his book Memoirs Illustrating the History of Jacobinism (original title Mémoires pour servir à l'Histoire du Jacobinisme) published in 1797. In short, Barruél claims that the French Revolution was planned and executed by the secret societies.
His basic idea was that of a very big conspiracy dating back through time, with the aim of overthrowing Christianity. It was to inspire John Robison , who had been working idependently on his own conspiracy theory, to extend his book Proofs of a Conspiracy Against all the Religions and Governments of Europe with several quotations from Barruél. This theory has grown wildly throughout history, and is still alive in several imaginative minds.
Among other things he called Adam Weishaupt "a human devil".
External link