In the Middle Ages this name was common in England due to the popularity of medieval tales about the Trojan War. It subsequently became rare, but was revived in the 20th century.
In some cases this name can be a short form of longer names that start with Leo, such as Leonard.
This name was common in Sweden and Denmark in the 1970s [1]. It rose in popularity in the English-speaking world in the 1990s, entering the top ten for girls in the United States in 2009. It was also popular in many other countries at that time. Famous bearers include American actress Mia Farrow (1945-) and American soccer player Mia Hamm (1972-), birth names Maria and Mariel respectively.