After Belsen reveals the deeply personal ways in which British and American Christians responded to and were affected by survivors of the Holocaust in the years immediately following the liberation of concentration camps. British and American Christians—men and women, army chaplains and relief workers, government officials and interfaith activists – listened to testimony, confronted postwar issues facing Jews, pioneered the fight against antisemitism, and reapproached their Christian faith as they encountered survivors. At camps like Bergen-Belsen, these encounters forced Christians to confront their long-held beliefs, their complicity, and the meaning of solidarity in the face of atrocity. Using neglected archives, private correspondence of British and American Christians, and interviews with their families, Robert Thompson pieces together stories that complicate the idea of Christian silence. He highlights the emotional and theological impact of direct witness – moments when Christian and Jewish lives intersected amid the devastation. In doing so, he also reveals the previously unheard voices of women relief workers and chaplains who offered care, challenged antisemitism, and began to reformulate their beliefs from the ground up. After Belsen is not only a moving contribution that unites Holocaust studies, religious history, and interfaith reflection but also a vital new perspective on how ordinary people responded to extraordinary horror and how their responses resonate today. Their previously untold human stories demonstrate how lived experience – not just institutional declaration – shaped postwar Christianity.