High Heels Were Originally Men's Shoes

Sometime around the 10th century, some enterprising soul in a horse-riding culture figured out that your foot would stay more firmly in the stirrups if your shoe had a bit of a raised heel.
The innovation spread quickly, and soon whole armies—of men—rode into battle wearing pumps.
By the 17th century, these shoes became a fashion trend in Europe;
since having a horse was a symbol of high status, wearing a high-heeled shoe meant you had the medieval equivalent of a Mercedes-Benz.
Both men and women of means wore heels until they ultimately fell out of fashion for men.