Black magic started Europe's most brutal witch hunts.

Why were women burnt as witchea? 

People who questioned the teachings of the christian church in the medieval ages were branded as 'heretics' and were often sentenced to death. The pope even set up a special court for this in 1234,called the inquisition. At the end of the medieval age, monks claimed that there were women, in alliance with the devil, who could cast 'evilspells' and were responsible for diseases and failed crops. Many people believed this, and when there was a crop failure, they tried to find some witch to blame.If they thought that a witch had been found, she was burnt at the stake. 

In the 1590s, King James I of Scotland's fear of witchcraft began stirring up national panics, resulting in the torture and death of thousands.

Witches at the stake were thought to be 'clearly' in alliance with the devil, who in the shape of a bird having a tail like a snake would try to abduct them.