Just saw a bit of a 1950s-era TV show on sources for provisions in the Bill of Rights. Among them was the story of the so-called “Man in the Iron Mask” – and no, I’m not talking about Leo here. Voltaire had written about this man who had been taken as a prisoner (apparently at the order of French King Louis XIV) around 1660. When he was being brought to the prison, a signal shot was fired that alerted the guards to turn their backs as the prisoner was brought in. The prisoner then lived out some 30 years in his metallic mask, and the circumstances of his imprisonment remain a mystery even today.

This story must have become well known during the Enlightenment, as the TV show I was watching said that it influenced the American Founders to include the prohibition against "cruel and unusual punishment" in the Eighth Amendment (Excessive bail shall not be required, nor excessive fines imposed, nor cruel and unusual punishments inflicted.). This was the first I'd heard of the connection between the Man in the Iron Mask and the U.S. Bill of Rights. Had anyone else heard this before? Bonus points + who is your guess as to the identity of the prisoner?