He has published on the history of psychological trauma, memory and masculinity in Germany during the age of total war. He is the author of An Intimate History of the Front: Masculinity, Sexuality and German Soldiers in the First World War (Palgrave Macmillan, 2014) and The Great War and German Memory: Society, Politics and Psychological Trauma, 1914-1945 (Liverpool University Press, 2009). He is also the co-editor, with Peter Leese, of the companion collected volumes Psychological Trauma and the Legacies of the First World War and Traumatic Memories of World War Two and After (both with Palgrave Macmillan, 2016).