The Man in the Iron Mask, by Alexandre Dumas, is a work of historical fiction based on a few generally established truths about a French prisoner during the late 1600s, the reign of Louis XIV. Here is the data most scholars and historians who have studied it have agreed on:
- There was a prisoner at the Bastille from at least 1698 (some have said as early as 1666) until 1703.
- It is possible that he was imprisoned elsewhere before he was transferred to the Bastille.
- The mystery prisoner died on November 19, 1703. His name, according to a death certificate, was Monsieur de Marchiel. He was approximately the same age as the king.
- The prisoner wore some kind of mask, probably made of black velvet but perhaps something metal.
- Because of the somewhat deferential treatment the prisoner was given, it seems likely the prisoner was a nobleman or perhaps even royalty.
Anything else is hearsay, at best. Dumas suggests that the man in the iron mask is there because he may know too much about the crimes of another--his brother, King Louis, who had to be sure his claim to the throne was not impugned.
A man is held to be criminal, sometimes, by the great ones of the earth,not because he has committed a crime himself but because he knows of one which has been committed.
Though this idea fits nicely into an adventure story, it is not wholly based on fact.