Was the Priory of Sion a real secret society?

No. The Priory of Sion was a fabrication created in 1956 by Pierre Plantard, a French draftsman with a history of founding small, obscure organizations and making grandiose claims about his ancestry. Plantard registered the Priory as an association in the subprefecture of Saint-Julien-en-Genevois in 1956, and its founding documents list only four members. The supposed medieval origins, the connection to the Knights Templar, and the list of famous Grand Masters (including Leonardo da Vinci, Isaac Newton, and Victor Hugo) were all fabricated. Plantard admitted under oath in 1993 that the documents were forgeries.

What are the Dossiers Secrets and why were they planted?

The Dossiers Secrets (Secret Files) are a collection of forged documents that were deposited in the Bibliotheque nationale de France during the 1960s. Created primarily by Philippe de Cherisey, a friend and associate of Pierre Plantard, the documents purported to contain genealogical evidence showing that Plantard was a descendant of the Merovingian dynasty and therefore a rightful heir to the French throne. The forgeries were designed to give Plantard's claims an appearance of scholarly legitimacy by placing them in a national research institution where future researchers might find and cite them — which is exactly what happened.

How did the Priory of Sion hoax become so widely believed?

The hoax gained credibility through a chain of credulity. In 1982, Henry Lincoln, Michael Baigent, and Richard Leigh published 'The Holy Blood and the Holy Grail,' which treated the Dossiers Secrets as authentic historical documents without adequate source criticism. The book became an international bestseller. Dan Brown then used the book as source material for 'The Da Vinci Code' (2003), which sold over 80 million copies worldwide. By the time Plantard's confession was widely known, millions of readers had absorbed the narrative as historical fact through these popular works.

Priory of Sion — Secret Society Guarding the Grail

Overview

The Priory of Sion (Prieure de Sion) is one of the most successful hoaxes of the twentieth century — a fabricated secret society that was presented as an ancient order guarding the bloodline of Jesus Christ and Mary Magdalene. Created in 1956 by French draftsman Pierre Plantard, the Priory was supported by forged documents planted in France’s national library and eventually became the foundation for two of the best-selling books of the modern era: The Holy Blood and the Holy Grail (1982) and Dan Brown’s The Da Vinci Code (2003).

The story of the Priory of Sion is debunked. Plantard confessed under oath in 1993 that the documents were fabrications. The French courts investigated and confirmed the forgeries. Every serious historian who has examined the evidence has concluded that the Priory’s medieval pedigree was entirely invented. Yet the cultural impact of the hoax has been extraordinary, embedding in popular consciousness a narrative about secret societies, suppressed bloodlines, and hidden religious truths that continues to influence conspiracy culture.

The Priory of Sion case demonstrates how a modest fraud, given enough time and the right popularizers, can become accepted as historical truth by millions of people — and how difficult it is to dislodge a compelling narrative even after its foundations have been proven false.

Origins & History

Pierre Plantard (1920-2000) was a minor figure in French fringe politics with a pattern of founding small organizations and making extravagant claims about his heritage. In the 1940s, he founded an organization called Alpha Galates, which promoted a vaguely reactionary, anti-Masonic agenda. He was investigated by French police and briefly imprisoned in 1953 for fraud.

In 1956, Plantard registered the “Priory of Sion” as an association in the subprefecture of Saint-Julien-en-Genevois in Haute-Savoie. The registration papers listed the organization’s purpose as mutual aid and the defense of the rights and freedoms of low-cost housing residents — a far cry from the medieval order guarding the Holy Grail that would later be described. The founding members numbered four.

During the 1960s, Plantard and his associate Philippe de Cherisey created a series of forged genealogical and pseudo-historical documents collectively known as the “Dossiers Secrets” (Secret Files). These documents were carefully deposited in the Bibliotheque nationale de France, where they would be catalogued and available to researchers. The forgeries purported to show:

That the Priory of Sion had been founded in 1099 during the First Crusade
That it had served as the secret power behind the Knights Templar
That its Grand Masters had included Leonardo da Vinci, Robert Boyle, Isaac Newton, Victor Hugo, and Claude Debussy
That the Priory guarded the secret of a surviving bloodline of Jesus Christ and Mary Magdalene, which had merged with the Merovingian dynasty of Frankish kings
That Pierre Plantard was a direct descendant of this lineage

The documents also incorporated the mystery of Rennes-le-Chateau, a small village in southern France where a parish priest named Berenger Sauniere had allegedly discovered ancient parchments and become inexplicably wealthy in the late nineteenth century. The Dossiers Secrets connected Sauniere’s supposed discovery to the Priory’s secrets.

Key Claims

The Priory of Sion is an ancient secret society founded in Jerusalem in 1099 by Godfrey of Bouillon
The organization’s purpose is to protect the descendants of Jesus Christ and Mary Magdalene, whose bloodline survived through the Merovingian kings of France
The Holy Grail (Sangreal) is not a cup but a reference to the “Royal Blood” (Sang Real) of this lineage
Leonardo da Vinci, Isaac Newton, and other famous figures served as Grand Masters who encoded the secret in their works
The Catholic Church has actively suppressed knowledge of Jesus’s marriage and descendants to protect its institutional authority
The Knights Templar were the military arm of the Priory of Sion before the two organizations supposedly separated in 1188
Plantard was a descendant of the Merovingian dynasty and therefore of the bloodline of Christ

Evidence

The Dossiers Secrets: The forged documents were real objects deposited in a real library, which gave them an air of legitimacy. However, forensic and historical analysis has conclusively identified them as twentieth-century fabrications. The paper, typefaces, and printing methods are consistent with mid-twentieth-century production. The genealogical claims contain anachronisms and errors impossible in genuine medieval documents. The list of Grand Masters was compiled from historical figures with no documented connection to any such organization.

Philippe de Cherisey’s Confession: Before his death in 1985, de Cherisey privately acknowledged his role in creating the forged parchments associated with Rennes-le-Chateau. His notes and drafts, which survive, show the process of fabrication.

Plantard’s Confession: In September 1993, during an investigation by French judge Thierry Jean-Pierre into the financial affairs of Roger-Patrice Pelat (a friend of President Mitterrand), Plantard was called to testify after claiming that Pelat had been a Grand Master of the Priory. Under oath, Plantard admitted that the entire organization and its history were fabrications. His home was searched, yielding documents that confirmed the hoax. He was given a severe reprimand and faded into obscurity until his death in 2000.

Historical Analysis: Professional historians including Marina Massimo Introvigne, Jean-Luc Chaumeil, and Paul Smith have thoroughly documented the fabrication. The supposed medieval history of the Priory cannot be corroborated by any independent historical source. No reference to the organization exists in any document predating Plantard’s activities in the 1950s.

Debunking / Verification

The Priory of Sion is classified as debunked. The key findings are:

Plantard confessed under oath in 1993 that the entire history was fabricated
De Cherisey acknowledged creating the forged parchments
The Dossiers Secrets have been forensically identified as twentieth-century forgeries
No independent historical evidence of the Priory exists before 1956
The list of Grand Masters is fabricated; no documentary evidence connects any of the named individuals to such an organization
The supposed genealogical connection between the Merovingians, the bloodline of Christ, and Plantard is entirely invented
Professional historians universally reject the claims

The debunking is complete and admitted by the hoax’s creator himself. What remains is not the factual question (resolved) but the cultural phenomenon (ongoing).

Cultural Impact

The Priory of Sion hoax had a cultural impact vastly disproportionate to its origins. The chain of transmission from hoax to cultural phenomenon followed a clear path:

In 1969 and 1970, Henry Lincoln, a British television writer, encountered the Rennes-le-Chateau mystery and the Dossiers Secrets. He produced three documentaries for BBC Two that treated the material as potentially authentic mystery. In 1982, Lincoln collaborated with Michael Baigent and Richard Leigh to publish The Holy Blood and the Holy Grail, which presented the Priory narrative as a serious historical hypothesis. The book became an international bestseller, translated into dozens of languages.

In 2003, Dan Brown published The Da Vinci Code, a thriller that used the Priory of Sion narrative as its central plot device. The novel opened with a page stating: “FACT: The Priory of Sion — a European secret society founded in 1099 — is a real organization.” The book sold over 80 million copies worldwide and was adapted into a 2006 film starring Tom Hanks.

The success of these works embedded the Priory narrative deep in popular culture, to the point where millions of people believe some version of the claims despite the thorough debunking. The case is frequently cited by media scholars as an example of how fiction can create persistent false beliefs, and how the packaging of claims as “suppressed history” can be more persuasive than their actual evidentiary basis.

The hoax also influenced broader conspiracy culture by popularizing the template of the “ancient secret society guarding forbidden knowledge,” a narrative framework that has been applied to numerous other alleged organizations.

Timeline

1885-1917 — Berenger Sauniere serves as parish priest at Rennes-le-Chateau; origins of the village’s mystery
1920 — Pierre Plantard born in Paris
1940s — Plantard founds Alpha Galates, makes early claims about aristocratic lineage
1953 — Plantard imprisoned for fraud
1956 — Plantard registers “Priory of Sion” as an association in Saint-Julien-en-Genevois
1960s — Plantard and de Cherisey create and plant the Dossiers Secrets in the Bibliotheque nationale
1969-1972 — Henry Lincoln produces BBC documentaries about Rennes-le-Chateau incorporating the Dossiers Secrets
1982 — Baigent, Leigh, and Lincoln publish The Holy Blood and the Holy Grail
1985 — Philippe de Cherisey dies, having privately acknowledged the forgeries
1993 — Plantard confesses under oath that the Priory’s history was fabricated
2000 — Pierre Plantard dies in Paris
2003 — Dan Brown publishes The Da Vinci Code, presenting the Priory narrative as fact
2006 — The Da Vinci Code film released; Baigent and Leigh unsuccessfully sue Brown for copyright infringement
Present — Despite complete debunking, the Priory narrative persists in popular culture

Sources & Further Reading

Introvigne, Massimo. “Beyond The Da Vinci Code: History and Myth of the Priory of Sion.” CESNUR, 2005.
Smith, Paul. “Priory of Sion.” Extensive research archive at priory-of-sion.com.
Putnam, Bill, and John Edwin Wood. The Treasure of Rennes-le-Chateau: A Mystery Solved. Sutton Publishing, 2003.
Baigent, Michael, Richard Leigh, and Henry Lincoln. The Holy Blood and the Holy Grail. Jonathan Cape, 1982. [Primary source of the popularized claims]
Chaumeil, Jean-Luc. Le Tresor du Triangle d’Or. Robert Laffont, 1979.
Bernstein, Richard. “Was the Priory a Hoax? The Authors Fight Back.” The New York Times, April 27, 2004.