The unearthing of the First Folio in France suggests Shakespeare may have had links with the clandestine Catholic worshippers who were brutally suppressed in England in the late 16th and early 17th century.
The well-preserved 233rd example, published seven years after his death in 1623; which has surfaced in the public library of the small town near Calais belonged until the French Revolution to a Jesuit college in the town.
Eric Rasmussen, the expert who authenticated the Saint-Omer First Folio, believes that the book may have crossed the Channel with Edward Scarisbrick, a prominent English Catholic who studied at Saint-Omer in the 1630s.
The first page is inscribed with the word 'Nevill'. Scarisbrick is known to have used the name 'Nevill' or 'Neville'.
Mr Rasmussen, the author of The Shakespeare First Folios: A Descriptive Catalogue, says that the discovery adds to the disjointed evidence that Shakespeare had links with the Catholic resistance in Elizabethan and Jacobean England .
"People have been making vague arguments, but now for the first time we have a connection between the Jesuit college network and Shakespeare," he told The New York Times. "The links become a little more substantial when you have this paper trail."
Martin Wiggins, a senior fellow at the Shakespeare Institute in Stratford-upon-Avon, dismisses the speculation about Shakespeare's supposed Catholic sympathies as "irrelevant". "He was admired and studied by English Catholics. We already knew that. Now we have more evidence. That doesn't mean that Shakespeare was himself a Catholic sympathiser," Dr Wiggins told The Independent.