Brown relies on the 1982 publication, Holy Blood, Holy Grail, for his information on the Priory of Sion. The authors of Holy Blood, Holy Grail relied on documents provided them by Pierre Plantard, who spend time in jail for fraud in 1953. Plantard and three other men started a small social club in 1956 called the Priory of Sion... Through the 1960s and the 1970s, Plantard created a series of documents 'proving' the existence of a bloodline descending from Mary Magdalene, through the kings of France, down to the present day to include (surprise!) Pierre Plantard.... In 1993... Plantard, under oath, admitted he had made up the whole Priory scheme.
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