Published on January 5, 2008
Slide1: Winston Churchill once wrote that, '... the only thing that ever really frightened me during the war was the U-boat peril'. Slide2: Germany's best hope of defeating Britain lay in winning the Battle of the Atlantic and Churchill correctly identified the importance of the threat posed by German submarines (the 'Unterseeboot') to the Atlantic lifeline which kept Britain fed. Slide3: If Germany had prevented merchant ships from carrying food, raw materials, troops and their equipment from North America to Britain, the outcome of WW II could have been radically different. Britain might have been starved into submission, and her armies would not have been equipped with American-built tanks and vehicles. Slide4: From the summer of 1940 the U-boat menace grew. This was in part because the conquest by Germany of Norway and France gave the Germans forward bases, which increased the range of the U-boats. Slide5: The British were consequently forced to divert their own shipping away from vulnerable UK ports, and were faced with the need to provide convoys with naval escorts for greater stretches of the journey to North America. The Royal Navy was critically short of escort vessels, although this problem was eased somewhat by the arrival of 50 old American destroyers that President Roosevelt gave in return for bases in British territory in the West Indies. Slide6: U-boats, supplemented by mines, aircraft and surface ships, succeeded in sinking three million tons of Allied shipping in 1940. Admiral Dönitz, the commander of the U-boat arm, introduced the 'wolfpack' tactic at the end of 1940, whereby a group of submarines would surface and attack at night. Not surprisingly, the German submariners called this phase of the war the 'happy time'. Slide7: The British survived this period through a number of factors, including the development of improved tactics, and the Allied occupation of Iceland, gave Britain some valuable Atlantic bases. More importantly, USA, although neutral, began to behave in a most un-neutral fashion Slide8: From May 1941 the US Navy became a British ally in the struggle in the Atlantic. By taking over escort duties in the western Atlantic, it became involved in a shooting war with Germany, and on Halloween 1941, the inevitable happened. While escorting a British convoy, an American warship, the destroyer Reuben James, was torpedoed and sunk by the submarine U-562. Eventually this undeclared German-American naval war probably played a role in Hitler's decision to declare war on the USA - in the aftermath of Pearl Harbor. Slide9: Apart from ships, two other factors played a vital role in the winning of the Battle of the Atlantic. The first was the airplane. One of the major problems faced by the Allies in the early years of the war was the existence of a 'mid-Atlantic gap', an area that could not be reached by friendly aircraft. The new idea of the Aircraft Carrier was thus born Slide10: The role of intelligence Intelligence was the other major factor. Britain's ability to break the Enigma codes, and the resulting 'Ultra' intelligence was a priceless advantage, particularly after the Royal Navy (not, as a recent Hollywood movie would have one believe, the Americans) seized an Enigma machine from a captured U-boat in May 1941. Armed with information about where U-boats were patrolling, the British were able to move convoys in safe areas, away from the wolfpacks. Slide11: The crisis of the Battle of the Atlantic came in early 1943. Döntiz, now had 200 operational U-boats. British supplies, especially of oil, were running out, and it became a question of whether Allied shipyards could build merchant ships fast enough to replace the tonnage that was being sunk. Slide12: At sea, the situation was saved by aggressive anti-submarine tactics, by new technology - better weapons and radio, and intelligence. By April the U-boats were clearly struggling to make an impact. Even worse, from Hitler's point of view, was the fact that Allied sinkings of German submarines began to escalate, with 45 being destroyed in the months of April and May. Döntiz, recognising that the U-boat's moment had passed, called off the battle on 23 May 1943. Slide13: The Battle of the Atlantic was one of the longest campaigns of World War Two, and it was proportionally among the most costly. Between 75,000 and 85,000 Allied seamen were killed. About 28,000 - out of 41,000 - U-boat crew were killed during World War Two, and some two-thirds of these died in the course of the Battle of the Atlantic. The stakes could not have been higher. If the U-boats had prevailed, the western Allies could not have been successful in the war against Germany.