None of this is new to sociologists. The presence of witchcraft in African cultures was explored by the anthropologist E.E. Evans-Pritchard. Pritchard wrote Witchcraft, Oracles & Magic Among The Azande in 1937 after his stay with the Zande tribes. Pritchard takes an interesting (if slightly condescending) view: the belief in witches is a sort of social lubricant that helps Zande society function. It enables "pre-logical" (his phrase) people to explain bad luck and setbacks. It enables neighbours to accuse each other and revenge themselves for real or imagined slights. The 'poison oracle' (feeding a poison to a chicken and seeing if it dies) reveals whether the accused has a witch inside them. If they do, then repentance follows. Nobody gets killed, although some people get terribly shamed for something they are in fact innocent of. Nevertheless, the society as a whole benefits from the safety valve witchcraft accusations provide.
Clearly, whatever positive value witchcraft beliefs might have had in Pritchard's day, they disappear when those beliefs involve the torturing and murdering of children (possibly, Pritchard's benign interpretation turned a blind eye to excesses in the 1930s too). Nonetheless, he does explain something: that witchcraft beliefs are functional and they serve a clear purpose for the community that engages in them. Nigerian immigrants in London skyrise estates (for example) experience a lot of dislocation, isolation and fear. Churches provide a focal point for their communities and help them hang on to their identity and culture. Witchcraft beliefs reinforce this, punishing those who stray, asserting belonging and purity, giving expression to fear. The fact that children are so often targeted is surely tied to an anxiety that the children are growing up 'different': they are assimilating, becoming culturally strange. In the European Middle Ages, beliefs in 'changelings' expressed similar parental anxieties born of stress - the delusion that the child is not your own, that it is evil or contaminated.
Nonetheless, most immigrants and most churches don't engage in these beliefs, so it's not enough to say 'Oh, it's religion!' or 'Oh, its East Africans!'.
The witch trials of the 1620s in Europe and Matthew Hopkins' trials in England in the 1640s are similarly baffling. They always seem to involve what sociologists all moral entrepreneurs. These are individuals who seize upon a cause before it is widely commented on and work hard to bring it to public attention and change social norms regarding this cause. Moral entrepreneurs worked to create public distaste for slavery, acceptance of rights for women and (in our times) the legalisation of gay marriages. Some moral entrepreneurs fail - like Mary Whitehouse in the 1970s, they are backward looking, fighting a rearguard action against social change. Other moral entrepreneurs succeed and their beliefs actually become new social norms - the widespread acceptance of homosexuality as a legitimate sexual orientation has taken place in British society over the last 30 years despite Government opposition in the '80s and '90s.
So, Matthew Hopkins could be seen as a moral entrepreneur, as could Fuchs Von Dornheim in Bamberg and Adolf Von Ehrenberg in Würzburg in the 1620s. Significantly, the Bamberg and Würzburg trials petered out as soon as those leaders fled or died. Although the Swedish invasion put a stop to those witch trials, that is hardly due to Swedish Protestantism being somehow more relaxed or liberal than German Catholicism. Moreover, when the Catholics returned to power, the witch trials did not resume either. Already, the Jesuit Fr Friedrich Spee was publishing his Cautio Criminalis and arguing passionately for the abolition of torture in witch trials. A believer in witches, Spee was convinced that not one of the victims in Würzburg or Bamberg was really guilty. Spee's blistering publication turned a corner for legal minds and similar changes were going on at a popular level.
In Tinderspark I depict Von Dornheim as simply venal - a fat, money-grubbing opportunist who uses witch scares to enrich himself and attack his enemies. Almost certainly, there were people like this and Von Dornheim's career was grubby indeed. Yet it doesn't really seem to do justice to the historical witch hunters and their zeal or their ability to inspire other people with the panic. In Alison Williams' The Black Hours, Matthew Hopkins is presented as a sexual inadequate and religious bigot. Again, such people exist and the two traits have been combined in the popular imagination ever since Freud. Nevertheless, I'm not convinced. Hopkins' horrid little pamphlet, A Discovery of Witches, barely mentions God or the Bible and doesn't show much interest in souls or righteousness. It reads like a technical manual or a nerd's blog. Hopkins clearly believed in what he was doing - he wasn't a hypocrite in the usual sense - but he comes across like a rabid Star Trek fanboy who is suddenly able to live out his obsession, not a religious enthusiast on a mission from God. Even his self-appointed title, Witchfinder General, smacks of the frustrated D&D player, not the frustrated saint or sex maniac.
In some ways I regret skewing The Burning Times so heavily towards fantasy. There's something interesting to be written on the witch trials without bringing in werewolves and angels. But then again, Arthur Miller already did that.