If you’ve spent much time here in the Margins, you know that I’m fascinated by historical boundaries: the times and places where two cultures meet (peacefully or, more often, not) and change each other. One of my favorite examples of a historical boundary is Islamic Spain, where Dar al Islam and Christendom met in exciting and productive ways. Recently I read a new book that shifted my vision of this period by several important degrees.

Popular conceptions about the role of religion in the Middle Ages take two basic forms. One version looks at the medieval world in terms of crusade, jihad and pogrom: a violent collision between mutually intolerant communities of Christianity, Islam and Judaism with long-term consequences for the modern world. The alternate vision, popularized in works such as María Rosa Menocal’s The Ornament of the World and focused specifically on medieval Spain, is that of the convivencia–a culture of mutual tolerance and reason. In Infidel Kings and Unholy Warriors: Faith, Power and Violence in the Age of Crusade and Jihad, religious historian Brian A. Catlos convincingly argues that neither image is adequate to understand the shifting political, economic, and religious alliances of the Mediterranean world from 1050 to 1200.

Catlos looks at the complex relationship between politics and religious identity in the medieval Mediterranean through the stories of men who straddled communal boundaries in pursuit of power. Muslim and Christian kings made alliances against common enemies of either (or both) religion. Latin Christians went on crusade against other Christians. Sunni Muslims declared jihad against Shi’ites. Jews served as governors, generals, and administrators in both Muslim and Christian kingdoms–and in one case came close to ruling a Muslim state. Mercenary warriors, including the legendary El Cid, switched sides whenever it was in their own interest.

Infidel Kings and Unholy Warriors is a fascinating and complex account of diversity, collaboration and conflict in the period when medieval Christianity met the Islamic golden age.

Well worth the read.

Much of this review previously appeared in Shelf Awareness for Readers.