During the first three Crusades, in addition to military forces, a large number of civilians, such as women and children, were enslaved by both Muslim and Christian forces. While recounting historical events, Muslim and Christian historians sometimes offered ethical judgments on this treatment of captives. This research attempts to examine the ethical perspectives of Ibn al-Athir and Fulcher of Chartres as individuals who were both religiously educated and important historians of the Crusades. Based on the findings of this research, each historian defended their co-religionists, but they generally held a critical view regarding the behavior of soldiers towards civilian captives. Ibn al-Athir's criticism of the actions of Muslim emirs towards captives, alongside a prevailing religious perspective, also had conscientious aspects. However, conscientious criticism of the abuse of captives is less evident in the book of Chartres, and religious bias largely overshadowed fair ethical judgment. The research method in this article is historical, and after presenting the historical context and events, the author describes and analyzes the ethical mindset of Muslim and Christian scholar-historians based on the way these historians expressed implicit judgments and the explicitness of their bias or criticism of the events carried out by historical actors.