The tenth to the thirteenth centuries in Europe saw the appearance of popular heresy and the establishment of the Inquisition, the expropriation and mass murder of Jews, and the propagation of elaborate measures to segregate lepers from the healthy and curtail their civil rights. These were traditionally seen as distinct and separate developments, and explained in terms of the problems which their victims presented to medieval society. In this stimulating book, first published in 1987 and now widely regarded as a a classic in medieval history, R. I. Moore argues that the coincidences in the treatment of these and other minority groups cannot be explained independently, and that all are part of a pattern of persecution which now appeared for the first time to make Europe become, as it has remained, a persecuting society. In this new edition, R. I. Moore updates and extends his original argument with a new, final chapter, 'A Persecuting Society'. Here and in a new preface and critical bibliography, he considers the impact of a generation's research and refines his conception of the 'persecuting society' accordingly, addressing criticisms of the first edition.