During the first half of the thirteenth century, the crusade was transformed into a most sophisticated institution. By developing such aspects as recruitment, finance, liturgy, and the legal rights and duties of crusaders the Roman Curia managed to make the crusade an immensely versatile, and a potentially effective, instrument of papal politics. As a devotional activity and an expression of aggressive religious power, the crusade had kept its original momentum throughout the twelfth century, despite the set-backs in the Holy Land in the 1180s. In fact, the crusading movement was more vigorous than ever during the early 1200s. It imposed its might against the main rival of the Roman Church within Christendom by conquering Constantinople, it now fully expanded its scope into warfare against heretics and enemies of the papacy, and it achieved one of its greatest successes by defeating the Spanish Muslims in the battle of Las Navas de Tolosa in 1212. The problems facing the crusading movement at the beginning of the thirteenth century were problems of growth and expansion. There was no lack of enthusiasm, nor was there an absence of opportunity and initiative, to transform crusading zeal into positive action. And yet, the flag-ship of the crusading movement, the negotium Terrae Sanctae, was in dire straits. The Third Crusade had failed dismally; few elements of the Fourth Crusade ever reached Palestine. Out of this period of recurring frustration with regard to crusading efforts in the East, concerns about the nature and practice of the negotium crucis were bound to arise.

The success or failure of the crusade was not considered ultimately to be in the hands of its participants.