The Introduction opens by establishing a central point of the book: that German military chaplains were physically present at sites of mass killing of Jews and other victims of the Holocaust and World War II. The 1941 massacre of Jewish children at Bila Tserkva in occupied Ukraine is described and analyzed using German and Jewish sources. The theme of power and legitimation, which runs throughout the entire book, is presented. Building from the killing at Bila Tserkva and the role of chaplains there, the chapter shows how the Wehrmacht chaplains had considerable power. They served to legitimize Hitler’s regime and its genocidal war and played a key role in creating a reassuring narrative of events for German soldiers, their families, and the chaplains themselves. Other themes introduced include systems and dynamics (the importance of the chaplaincy as an institution), the forces of war and the confusion it generates, and habit: chaplains’ actions and decisions even before the war set patterns that became entrenched. The sources and methodology are explained, with emphasis on integrating Jewish sources.