Book excerpt: The Mongols had a huge impact on medieval Europe and the Islamic world. This book provides a comprehensive survey of contacts between the Catholic West and the Mongol world-empire from the first appearance of Chinggis Khan’s armies in 1221 down to the death of Tamerlane (1405) and the battle of Tannenberg (1410). This book considers the Mongols as allies as well as conquerors; the perception of them in the West; the papal response to the threat (and opportunity) they presented; the fate of the Frankish principalities in the Holy Land in the path of the Mongol onslaught; Western European embassies and missions to the East; and the impact of the Mongols on the expanding world view of the maturing Middle Ages. For courses in crusading history and medieval European history.