This thesis studies the involvement of women in the four great armed pilgrimages, the crusades of 1096-1204. A crusade was a pilgrimage, an act of penance for the sins of its participants, as well as being a holy war. Women were entitled to join pilgrimages because it was an act they had enjoyed for centuries. When, therefore, the armed pilgrimage was preached by Urban II in 1095, women too were permitted to journey although it was not anticipated at first by the papacy that they would. The presence of women in ritually pure camps and on the battlefields was objected to. The biblical beliefs of chroniclers and moralists of the period held that the presence of women on these campaigns compromised their purpose. This thesis will examine in primary sources the beliefs of the moralists and writers of the crusades, and the responses to the presence of women on campaigns.