They were known as “iron coffins”—the German U-Boats that terrorized Allied shipping during World War II. In this volume commemorating the fiftieth anniversary of the Battle of the Atlantic, historians from both sides of the ocean offer new insights into the conflict.The Battle of the Atlantic was the most important campaign of the war, for Allied success in Europe depended on massive movements of ships, men, and matériel across the Atlantic from the Americas. In spite of an unprecedented Allied shipbuilding effort, German U-boats were causing severe damage to this vital supply line; unless the deadly U-boat menace could be eliminated, the Allies would be unable to defeat Nazi Germany.The cost in lives lost and ships sunk was appalling, but statistics alone do not reflect the human dimension of this most terrible sea fight. It is a story of incredible courage and unspeakable cruelty, one in which calculated risks and life-or-death decisions became commonplace. It is a story of the combined efforts of planners and strategists, spies and codebreakers, naval officers and crews, merchant mariners, and civilians at home in both Allied and Axis nations to achieve an end to the carnage at sea. And it is a story of the triumph of technology, as Allied advances in radar and sonar ultimately led to victory over the German wolfpacks.The book makes an important contribution to the history of World War II, examining both much-studied and lesser-known aspects of this critical campaign. Its contributors provide a comprehensive account of all who participated in this long and costly effort: those who planned, those who fought, those who waited, and those who died.