This book explores the interplay between war and environment in Henan Province, a hotly contested frontline territory that endured massive environmental destruction and human disruption during the conflict between China and Japan during World War II. In a desperate attempt to block Japan's military advance, Chinese Nationalist armies under Chiang Kai-shek broke the Yellow River's dikes in Henan in June 1938, resulting in devastating floods that persisted until after the war's end. Greater catastrophe struck Henan in 1942-3, when famine took some two million lives and displaced millions more. Focusing on these war-induced disasters and their aftermath, this book conceptualizes the ecology of war in terms of energy flows through and between militaries, societies, and environments. Ultimately, Micah Muscolino argues that efforts to procure and exploit nature's energy in various forms shaped the choices of generals, the fates of communities, and the trajectory of environmental change in North China.