Never before nor since has the Royal Navy been so challenged as it was during 1939-45. In the Atlantic it fought the longest campaign of the war against the German U-boats and surface ships, experiencing tragedy and triumph before the battle was finally won. The Mediterranean witnessed its one major fleet action of the war, and the grim struggle to prevent the crucial island of Malta from falling to the Axis. In the war against Japan the Royal Navy had to overcome early setbacks, but its Pacific Fleet played its part in bringing about ultimate victory.