11. Iron Mask Prisoner
Nobody knows what’s behind that mask! Looks like a mystery as of “the Mountain” in the GOT, isn’t it? He was an unknown prisoner who identity is not discovered. No one knew who was the real man in the iron mask. He was in prison in mid-1700’s. The masked man did not leave any clues behind who was he and what he was hiding!
12. Walter Haut
This guy who worked for US defense happened to witness a UFO! But eventually, it was told that he mistook a high-altitude weather balloon to be the UFO…However, after some years, he gave an interview describing the alien activities that he had witnessed on that night! The truth, well, remains unclear!
13. Green Children of Woolpit
Forgive me! But I could not miss this from the list of the Mysterious men, they may not be men, but these children are certainly way more mysterious than any other! In the 12th century, two children, brother, and sister, having unusual green skin suddenly appeared in the village of Woolpit in Suffolk. They spoke an unknown language and ate nothing except the beans only. Soon, they learned the English language and started to eat other foods. The green color of their skin also gone away with time. The boy was sick and died, but the girl claimed they came from a place called St Martin’s Land which is located underground world. The sun never shone there and everything there is green. Nobody ever found their origins!
Well, you can research on these mysteries and solve some if possible! Who knows, you might get successful!