When, in October 1517, Martin Luther pinned his Ninety-Five Theses to the door of All Saints' Church in Wittenberg, he shattered the foundations of western Christendom. The Reformation of doctrine and practice that followed Luther's seismic action, and protest against the sale of indulgences, fragmented the Church and overturned previously accepted certainties and priorities. But it did more, challenging the relationship between spiritual and secular authority, perceptions of the supernatural, the interpretation of the past, the role of women in society and church, and clerical attitudes...