Werewolves are man-wolves— wer is Old English for "man." Legends from around the world tell of men who could turn into wolves and then back into human form again. In their animal form, werewolves were bloodthirsty creatures that devoured people, both living and dead.
Legends of people changing into animals occur in all parts of the world. In countries where wolves are unknown, such legends have involved tigers, leopards, hyenas, bears, panthers, snakes, boars, and other animals. Perhaps these stories reflect a universal unease about the more bestial aspects of human nature and behavior. Some scholars have suggested that these transformation legends are faint echoes of ancient ceremonies in which people wore animal skins and masks.
European werewolf tales date from ancient times. Among other stories, Ovid* wrote that a Greek king named Lycaon was turned into a wolf as punishment for serving human flesh to the gods. From the Greek words lukos (wolf) and anthropos (man) comes lycanthropy, which refers to the werewolf's transformation. Modern psychologists also use the term to describe a mental illness in which the patient believes he or she is a wolf or some other animal.
Belief in werewolves was widespread in Europe during the Middle Ages. Any infant born with body hair, a strange birthmark, or a caul (a membrane covering the head) was thought to be a potential werewolf. It was believed that a person could become a werewolf voluntarily, generally by embracing black magic or worshiping the devil. The bite of a werewolf could also turn someone into a werewolf.
One of the most frightening aspects of werewolf legends was the idea that the cannibalistic beast could pass his days as a mild and righteous citizen, unsuspected of any evil. In some traditions, the werewolf took on animal form at will, perhaps every night. Other traditions, however, said that the transformation occurred only on nights of the full moon.
Folktales offered various tips about how to injure or kill a werewolf. Some suggested that any weapon that could hurt an ordinary wolf could harm a werewolf as well and that when the beast returned to its human form, its injuries would reveal its identity as a werewolf. Other legends said that only special weapons made of silver or possessing religious powers or blessings could harm a werewolf.