The Great War of 1914-1918 exploded on the European scene with unimaginable violence. Troops of all countries began the conflict using tactics and strategy of a bygone era. However, technology had produced weapons of war far advanced from the simple firearms of the last century. Infantry were cut down in heaps, and injuries to survivors were magnitudes more dangerous than before. Physicians and scientists quickly mobilized to employ laboratory methods to clinical medicine and surgery to address the horrible suffering of those mutilated boys and men struck down in the fields of France. Surgeons moved to near the front lines to deliver life- and limb-sparing treatment. For the first time, blood loss was treated by blood replacement. Bacteriology finally shed light on the threats of gas gangrene. Measures were taken to shield against the dangers of toxic gas attacks, and simple splints were employed to immobilize deadly fractures of the leg. Behind the front, innovative surgical techniques rescued countless victims of brain trauma, and skillful reconstructive surgeons rebuilt otherwise disfiguring facial injuries. And in those many veterans of the war so hobbled mentally by the trauma they had witnessed, doctors beneficently and slowly helped untangle the ravages of “shell shock”, what we now know as post-traumatic stress syndrome. To add insult to injury, a plague of influenza swept over armies of both sides and felled almost as many as bullets had. This is a book about tragedy but also about ingenuity, perseverance, and the collaborative efforts of governments, industries, and science to advance medicine into the Twentieth Century and beyond.