Although its main World War II commitment was in the Pacific, the U.S. Navy nevertheless made an indispensable contribution to defeating Germany in the Atlantic.
The Battle of the Atlantic—the World War II struggle for control of Atlantic Ocean convoy routes—was actually a series of naval campaigns of varying lengths that began in September 1939 and lasted until Germany's surrender in May 1945. While the Atlantic was the crucial naval theater of the war for Great Britain and its Commonwealth partner, Canada, the Pacific was America's chief naval theater. Nevertheless, the U.S. Navy's material, technological, and operational contributions were vital in defeating the U-boat onslaught against shipping. In the end, Allied victory in the Atlantic required the combined efforts of Britain, Canada, and the United States.