This book takes on the current vogue in liberal thinking to argue that, in fact, the Crusades were not unprovoked. They were not the first round of European colonialism. They were not conducted for land, loot, or converts. The Crusaders were not barbarians who victimized the cultivated Muslims. They sincerely believed that they served in God's Battalions.

In the wake of many recent books justifying Muslim holy wars by criticizing the historic use of violence by Christians, Stark presents the other side of the story. Drawing upon a wide variety of sources, Stark argues the facts and figures about why and how Christianity attempted to secure the Holy Lands and protect the safety of Christian pilgrims.