At the end of World War I, during the armistice proceedings in Germany and at the Peace Conference after the war, French General Maxime Weygand served as chief aid to Marshal Foch. Called out of retirement in the mid - 1930s, Weygand again served his country during World War II, first as French chief of the Mediterranean theater and later as commander in chief of the French Army. His forward-looking military theory, which called for enhanced French unity, military preparedness, and adaptation to a new kind of war dominated by tank mobility, would have likely saved France the humiliating 1940 defeat at the hand of the Nazis, had it been heeded. This ahead-of-its-time military strategy along with Weygand's immediate recognition of the Nazi threat earned him the respect of contemporary world leaders such as Winston Churchill and Franklin Roosevelt.Weygand's Vichy Resistance led to his imprisonment from late 1942 through the end of the war. French archival sources, available oral testimony and Weygand's private papers, particularly his detailed World War I diary, contribute to a fascinating biography of one of World War II's unsung heroes.