In a global Middle Ages, there are few individuals, fictional or historical, who have exercised a stronger cosmopolitan pull than Prester John. A product of anxious cultural imaginings mixed with hope for historical change, Prester John has commanded consistent interest since 1145. Over the course of six centuries, Prester John figured centrally in Christendom's understanding of what the distant world was like: crusading aspirations depended on his materialization; missionary undertakings in the East leveraged their chances of converting the heathen against a presumption of his existence, and, mercantile-minded men from Marco Polo through Christopher Columbus dreamt of the putative riches of his kingdom. 2 From its inception in the twelfth century, the Prester John legend linked the impulse to explore a global landscape with the desire for this landscape to be revealed as a continuation of, rather than a departure from, the known: as already Christian. Nowhere is this better expressed than in the original Latin Letter, the primary source for the legend of John. Produced in the mid-twelfth century at the zenith of the Crusading impulse, 3 the legend situates John as a Christian sovereign ruling authoritatively over an East that is beyond Dar al-Islam and, despite its exotic and strange landscape, remains decidedly Christian.