Accusations of heresy did not arise in a vacuum during the Middle Ages. Polemicists and inquisitors had their own agendas, often involving lay or ecclesiastical politics. Heresy and treason became equated by the thirteenth century, opening the way for stronger measures against dissenters. The present volume addresses the myriad ways in which heresy accusations could be employed to fulfill political aims, from managing the effects of intellectual dissent on popular movements, to manipulating the heresy topos, to mediating the large-scale relationship between ecclesiastical and secular politics, both in Christendom and in the Islamic world.