The link between fundamentalist religion, violence, and madness is well established. The conviction of absolute truth becomes especially toxic when believers are convinced that the end of the world is nigh. This is exacerbated in times of major socio-economic change and political instability, such as during the Protestant Reformation.

Paul Ham’s New Jerusalem vividly illustrates this. It tells the bizarre story of the most radical of the Reformation’s reformers, the Anabaptist sect that seized the city of Münster between 1534 and 1535. What started as a peaceful apocalyptic movement transmuted into a religious monstrosity. Much more than a heretical sect, they ‘stoked civil unrest’ and were, as Ham says, ‘a deeply subversive political and economic movement’, which helps explain the ferocious vengeance that was afterwards wreaked upon them.