How do people of different religious faiths interact? How do they create professional and personal relationships—and what limits are placed on those relationships, either by law or by the individuals themselves? Conversely, what causes hostility and violence between faiths? This course investigates these eternal questions through an in-depth study of relations between Christianity, Judaism, and Islam in the medieval Mediterranean world. We will begin with the earliest interactions between these religious traditions, as Christianity and Judaism diverged from common roots into separate faiths in the first two centuries CE, and as Islam emerged in the seventh century. In our second unit, we will study medieval Spain, where Christians, Jews, and Muslims coexisted relatively peacefully for centuries, but where that toleration crumbled in the later Middle Ages, culminating in the Spanish Inquisition.