Man in the Iron Mask has also been proposed as the man in the mask. A Protestant, he led a rebellion against his uncle, the Catholic King James II. The rebellion failed and Monmouth was executed in 1685. But in 1768, a writer named Saint-Foix claimed that another man was executed in his place and that Monmouth became the masked prisoner, it being in Louis XIV's interests to assist a fellow Catholic like James who would not necessarily want to kill his own nephew. Saint-Foix's case was based on unsubstantiated rumours and allegations that Monmouth's execution was faked. Other popular suspects have included men known
Man in the Iron Mask the enquiry the investigators were told about a supplier of poisons, a surgeon named "Auger", and Duvivier became convinced that Dauger de Cavoye, disinherited and short of money, had become Auger, the supplier of poisons, and subsequently Dauger, the man in the mask. In a letter sent by Louvois to Saint-Mars shortly after Fouquet's death while in prison (with Dauger acting as his valet), the minister adds a note in his own handwriting, asking how Dauger performed certain acts that Saint-Mars had mentioned in a previous correspondence (now lost) and "how he got the drugs necessary to do so". Duvivier