A spirited and sweeping account of how the crusades really worked-and a revolutionary attempt to rethink how we understand the Middle Ages. The story of the wars and conquests initiated by the First Crusade and its successors is itself so compelling that most accounts move quickly from describing the Pope's calls to arms to the battlefield. In this highly original and enjoyable new book, Christopher Tyerman focuses on something obvious but overlooked: the massive, all-encompassing, and hugely costly business of actually preparing a crusade. The efforts of many thousands of men and women, who left their lands and families in Western Europe, and marched off to a highly uncertain future in the Holy Land and elsewhere have never been sufficiently understood. Their actions raise a host of compelling questions about the nature of medieval society. How to Plan a Crusade is remarkably illuminating on the diplomacy, communications, propaganda, use of mass media, medical care, equipment, voyages, money, weapons, wills, ransoms, animals, and the power of prayer during this dynamic era. It brings to life an extraordinary period of history in a new and surprising way.