In 1095, Pope Urban II called for Western European Christians to wage a holy war to reclaim Jerusalem from the Muslims. Those who served as "soldiers of Christ," the pope said, would be cleansed of sin. Within several months, 100,000 men and women, from virtually all stations of life (no kings volunteered), answered the call. Their religiously motivated and violent actions set in motion events that radically transformed the relationship between Christians and Muslims; the reverberations are still with us. Thomas Asbridge, a British scholar and Crusade historian, tells the story of the three-year, 3,000-mile journey in his magnificent The First Crusade: A New History. Working from firsthand accounts and the latest Crusade scholarship, Asbridge skillfully combines religious and military history, challenging long-held views in the process. "The crusade was designed, first and foremost, to meet the needs of the papacy," he writes, "the campaign must be seen as an attempt to consolidate papal empowerment and expand Rome's sphere of influence." The crusaders themselves had many motives for undertaking the journey; Asbridge is convinced that greed was not a primary one. Recent research shows how incredibly expensive and extremely frightening the journey was. He does note, however, that "perhaps the most significant insight into the medieval mentality offered by the First Crusade is the unequivocal demonstration that authentic Christian devotion and a heartfelt desire for material wealth were not mutually exclusive impulses in the eleventh century."The First Crusade reached its nadir in June 1098 at the Great Battle of Antioch. Death, hunger, threat of a Muslim attack and a morale crisis appeared to signal defeat. It was only the discovery of a small shard of metal thought to be part of a Holy Lance an event interpreted as a "miracle" that, along with gifted leadership and a lot of luck, inspired the crusaders to achieve a stunning victory against all odds. Asbridge's excellent account of the first Crusade is consistently enlightening. Roger Bishop is a Nashville bookseller and a regular contributor to BookPage.