Witchcraft persecution (as with any religious persecution) was more of a financial endeavor than a religious concern. Most of the old practices were forced underground for survival when nature oriented religions encountered the militant Christianity. Instead of toleration, Christianity used an assimilation of Witchcraft traditions. One of the only exceptions of this practice is the Jehovah Witness; they reject all Holidays and practices that have even remote connections to Paganism and Witchcraft.
Christianity, still following the belief of the Great Mother Goddess, spread to Ireland and Britain around the 5th century AD. Pope Gregory the Great realized that Christianity could not overthrow these deeply rooted ancient rites, so he instructed his priests to include these rituals in their Christian ceremonies.
Christians soon grew suspicious of the ceremonial herbal drinks; they believed them to be magic potions. They thought that people wearing animal skins would actually turn into the animal. The Christians also feared anyone who looked to the future.
Witches were organized into groups called covens. Each coven consisted of 12 members and a priest. The leader was usually a man dressed in animal skin and horns that represented the Horned God; this looked like the Devil to many Christian people.
Witchcraft was used to explain frightening phenomena, like illness or storms. Witches were mentioned in the Bible, more people in the past believed in the Bible literally than do today. Religious leaders told the people that witches were doing the Devils work here on earth.
According to old stories, a witch made a deal with the Devil to do his bidding. To make the agreement official, she would sign her name in the Devil's book and he put his mark on her body, usually with his claw. The mark was usually a mole or a scar that was thought to be cold and dead. . These mark's were on hidden places, such as on the eyelids or the armpits and given at the end of initiation rights held at meetings called Sabbats.
The Sabbats took place on moonlit nights on mountains and in forests or caves. After the "services" of Devil worship, there would be feasting and dancing, with witches flying home before dawn, usually on broomsticks. It was believed the Witches said their sermons backwards opposed to the Christian's forward sermons. The Christian sermons are quiet and calm but supposedly the Witches sermons were wild and crazy.
Once the witch agreed to the Devil's deal, she would gather souls for him by pestering and plaguing good people until they were willing to sign his book too. The Devil assigned each new members a "familiar" who were demons of a lower rank and assumed the shape of a common animal, i.e., cat, dog, bird particularly black cats. These familiars assisted witches in bewitching their victims.
Some people have said that the Devil gave a broom and a flying ointment to all the new witches as a part of initiation. It was thought that witches rode their brooms to Sabbats with their familiars. If they rode out to sea they would stir up storms. Farmers sat out pitchforks in fields to kill witches who fell off their brooms flying over their fields.