Histories of heresy published in the early modern period laid the foundation for our attitudes toward difference, deviance, and defiance of orthodoxies. We cannot understand modern notions of tolerance without understanding the mentalities that led to persecution, and how they changed. Many of these mentalities were forged and reforged in polemics against and histories of heresy. This is the first volume to analyze and compare a broad range of histories of heresy written in the seventeenth and eighteenth centuries. Its chapters show how authors could mean to justify persecution of heretics, or oppose it. Readers could read these volumes in accord with or against the intentions of their authors. The cumulative effect is a better understanding of the complex and contentious history of the historiography of heresy in this period, and a sense for its lasting effects.