6. Chastity belts
While we are on the subject of Middle Ages, here is another one of the history myths that originated later than we think. Chastity belts have come to be associated with medieval times (in particular, the Crusades), but there is no evidence that they even existed in that time period. The only mention of a chastity belt in medieval times is found in a 15th century humorous treatise about fictional inventions, hinting that the idea of forcing a woman to wear a metal girdle sounded just as ridiculous to medieval folks as it does to us now.
It was only later that historians stumbled upon the joke and decided to give it a new spin. Chastity belts became an illustration for the barbaric customs of medieval civilizations, completely unacceptable, of course, in the eyes of the enlightened people of the 18th century. However, in the end the joke was on the enlightened civilization: Victorians decided that chastity belts were a neat idea and proceeded to design a male version for anti-masturbatory purposes. It’s said to have been quite popular among the parents of teenage boys.