The Prieur de Sion, usually rendered in English translation as Priory of Sion or Priory of Zion, has, since the 1970s, been an elusive protagonist in many works of pseudohistory. It has been characterized as anything from the most influential secret society in Western history to a modern Rosicrucian-esque ludibrium, but, ultimately, has been proven to be a hoax created by Pierre Plantard. Most of the evidence presented in support of claims pertaining to its historical existence, let alone significance, has not been considered authentic or persuasive by established historians, academics, and universities.
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Pierre Plantard with help from others created the Priory of Sion in 1956 with a genealogy list proving he was a descendant of the French Merovingian Kings who claimed royal blood, SANGREAL, descent from Jesus and Mary Magdalene.
Plantard claimed he was elected Grand Master of the Priory of Sion in 1981, and much of Baigert, Leigh, and Lincoln's "HOLY BLOOD,HOLY GRAIL is based on Plantard's DOSSIERS SECRETS's fabricated genealogy lists.
"What eventually emerges from the welter of names, dates, maps, and genealogical tables crammed inti "HOLY BLOOD,HOLY GRAIL" is a yarn about a secret and hugely influential society called the Priory of Sion, founded in Jerusalem in 1099...
All the usual suspects and accouterments of period history get caught up in this thousand year jaunt. The Cathar heretics, the Knights Templar, the Rosicrucians, the Vatican, the Freemasons, Nazis, the Dead Sea Scrolls, the Protocols of the Elders of Zion, the Golden Dawn- everyone except the Abominable Snowman seems to be in on this game. "HOLY BLOOD,HOLY GRAIL is a masterpiece of insinuation and supposition , employing all the techniques of pseudohistory to symphonic effect..."
-Laura Miller, NEW YORK TIMES BOOK REVIEW, February 22, 2004
Much of the "evidence" presented on this thread of the Templars in Nova Scotia/Oak Island originated from Plantard's fabrications and the quasi alternative history created by Baigent, Leigh, and Lincoln and those who joined the fantasy ride of conspiracy history, Picknett and Prince.