Pope Innocent IV and Holy War

In the mid-thirteenth century, the rise of the Mongol Empire captivated Christian contemporaries in Western Europe, filling them with dread of the relentless “Tartars,” but also with hope for their possible conversion to Christianity. This European encounter with the Mongols has likewise fascinated modern historians of crusade and mission, who argue that—whether as targets for crusading violence or proselytizing—the Mongols opened a new chapter in Christian Europe’s relationship to the outside world. Christian Europe, however, did not speak with one voice during the mid-thirteenth century. To the contrary, at the time “Christendom” experienced a profound, disruptive struggle between the Pope Innocent IV and Emperor Frederick II, part of an ongoing medieval contest between papacy and empire for a position of leadership over Christian society. This paper will explore how the pope, the emperor, and their respective supporters seized upon the unexpected inroads of the Mongols to agitate for their own particular vision of Christendom, subordinating the demands and opportunities of the outside world to the immediate conflict within their own backyard.