At the War Archive in Vincennes is kept the File Copy of an Arrest Warrant. It's dated July 28, 1669. And it says this [from the Marquis de Louvois]: “Captain de Saint-Mars, I am sending you my prisoner to Pignerol in the charge of the Sergeant Major of my town and citadel of Dunkirk, the man named [name omitted].”

The actual Order has survived. This is the Copy of the original document which was sent to Saint-Mars. Notice that the name has been inserted in a different hand – not the clerks who wrote it, and the man's name is Eustache Dauger.

A diary – now held in the Arsenal Library in Paris – was Published in 1761. It had been kept unofficially half a century earlier by man named Etienne Du Junca. Du Junca had been the Bastille's second in command – his was the first-real first-hand evidence of someone who actually saw and was involved with The Man In The Mask. In 1698, he had recorded the arrival of the new Governor of the prison, a man called Saint-Mars.

“Thursday the 18 September, at 3 o'clock in the afternoon, Monsieur Saint-Mars, Governor of the Chateau of the Bastille arrived for the first time. Coming from his government of the Isle Sainte-Marguerite Honorat, and bringing with him in his litter, a long-term prisoner whom he had at Pignerol, and whom he keeps always masked, and whose name is never uttered.”

Du Junca wrote five years later: “The 19 November 1703. The unknown prisoner, always masked in a mask of black velvet, whom Monsieur de Saint-Mars the Governor had brought with him when he came from the Isle de Saint-Marguerite, and whom he had guarded for so long, died on this day.” [“…and was quickly buried under the name of Marchioly” – omitted from Timewatch S7 E3, 1988.]

Paul Sonnino's incredibly boring book, “The Search For The Man In The Iron Mask: A Historical Detective Story” (2016), that suggests the explanation for Eustache Dauger lay in the complicated intricacies of the Ancien régime and the financial corruptions that existed within the French Aristocracy, acknowledges that Dauger was arrested in Dunkirk on July 28, 1669; and that he was a Valet dealing with such delicate financial matters.

Henri II, Duke de Guise died in 1664.
Eustache Dauger was arrested in 1669.
Camille Bartoli's theory was wrong.