This volume contains thirty-four essays on a theme that is important for scholars of the Middle Ages, and appealing for the lay public, due to the mystical and romantic connotations of crusaders, Templars etc. The authors, specialists from 15 countries present various facets of the struggles waged for the possession of the Holy Land between the tenth and thirteenth centuries and of the activities of the military orders elsewhere in Europe. The articles focus on the development of the crusading idea and on the transformations of military orders. Special emphasis was given to represent different areas of Europe including, Western, eastern and South-eastern parts of the continent and the late Baltic crusades as well. Different methodological approaches (church history, archaeology, military history) highlight different aspects of the crusading experience and the interactions, co-habitation and warfare of different cultures and religions.