Here's something interesting: tucked away at the end of this article about witch burning is a piece which refutes the commonly held view that witch burning was orchestrated and encouraged by the Church:
In her paper, Recent Developments in the Study of the Great European Witch Hunt, Jenny Gibbons notes that most witch-hunts took place where central authority had broken down, often in border areas "where rival Christian sects fought to impose their religious views on each other". It was partly for this reason that local secular courts meted out the harshest judgements.
In countries like Spain, Italy and Russia, where a strong, unified Church existed, there were few witch trials.
On the other hand, Hallowe'en is the devil's work, Catholic church warns parents. Ah well.