The "Man in the Iron Mask" was a mysterious prisoner in France during the late 17th century. He was held in various prisons, including Bastille and Pignerol, and is famous for wearing a mask, which some believe was made of iron. His true identity remains unknown, leading to numerous theories about who he might have been, including claims that he was a royal twin or a political prisoner. The story gained popularity through literature and film, inspiring works by authors like Alexandre Dumas. The legend highlights themes of secrecy and injustice, capturing the imagination of many. Despite extensive historical research, the identity of the man remains one of history's enduring mysteries.