The capture of Jerusalem by the First Crusade in 1099 signalled the beginning of an armed struggle in Palestine and throughout the Eastern Mediterranean which lasted until the 15th century. It was a war dominated by the building, securing and besieging of castles rather than by pitched battles. Kristian Molin covers the military history of the crusades on a wider geographical scale than previous historians, taking in Armenia, Cyprus and Greece as well as the Holy Land. He also shows the role of castles as administrative, judicial and social centres in times of peace as well as in war. "Unknown Crusader Castles" provides a fresh perspective on the history of the crusades.