“The Sins of the Sons of Men”: A New Letter of Pope Celestine III Concerning the 1195 Crusade of Alarcos

Abstract

The discovery of a previously unknown and unedited letter sent by Celestine III to the bishops of the Iberian Peninsula in March 1195 reveals the efforts Rome made to organize a collaborative crusade against the Almohad Empire. The letter illuminates the mechanisms that the pope could deploy to encourage and coerce the kings of Christian Spain into cooperation and pursuit of goals endorsed by the Church. In addition to enhancing our understanding of the campaign that culminated in the Almohad victory over the Castilians at the battle of Alarcos in July of that same year, the letter provides another example of the peace-making efforts that the papacy undertook in the promotion of crusading.