It was largely in the Middle Ages that the black cat became affiliated with evil. Because cats are nocturnal and roam at night, they were believed to bemsupernatural servants of witches, or even witches themselves.
Folklore has it that if a witch becomes human, her black cat will no longer reside in her house.
Some believe that black cats are witches in disguise, or witches reborn.
Others believe black cats are witches familiars (beings that aid witches in performing their craft). Not all familiars were black cats though; some were cats of other colors, dogs, pigs, or other animals.
Some believe Cats are unworldly and can travel between the veils.