The U.S.-Dakota War, the bloodiest Indian war of the 19th century, erupted in southwestern Minnesota during the summer of 1862. In the war's aftermath, a hastily convened commission of five army officers conducted trials of 391 Indians charged with murder and massacre. In 36 days, 303 Dakota men were sentenced to death. In the largest simultaneous execution in American history, 38 were hanged on a single gallows on December 26, 1862 -- an incident now widely considered an act of revenge rather than judicial punishment. Providing fresh insight into this controversial event, this book examines the Dakota War trials from the perspective of 19th century military law. The author discusses the causes and far-reaching consequences of the war, the claims of widespread atrocities, the modern debate over the role of culture in lawful warfare, and how the war has been depicted by historians.