Monsun Gruppe

The Gruppe Monsun or Monsoon Group was a force of German U-boats (submarines) that operated in the Pacific and Indian Oceans during World War II. Although similar naming conventions were used for temporary groupings of submarines in the Atlantic, the longer duration of Indian Ocean patrols caused the name to be permanently associated with the relatively small number of U-boats operating out of Penang, (with its capital, George Town). After 1944, the U-boats of the Monsun Gruppe were operationally placed under the authority of the Southeast Asia U-boat Region.

The Indian Ocean was the only place where German and Japanese forces fought in the same theatre. To avoid incidents between Germans and Japanese, attacks on other submarines were strictly forbidden. Altogether 41 U-boats of all types including transports would be sent; a large number of these, however, were lost and only a small fraction returned to Europe.

The Indian Ocean was considered strategically important, containing India, and the shipping routes and strategic raw materials that the British needed for the war effort. In the early years of the war German merchant raiders and pocket battleships had sunk a number of merchant ships in the Indian Ocean; however as the war progressed it became more difficult for them to operate in the area and by 1942 most were either sunk or dispersed. From 1941, U-boats were also considered for deployment to this area but due to the successful periods known as the First and Second Happy Times, it was decided that sending U-boats to the Indian Ocean would be an unnecessary diversion. There were also no foreign bases in which units could operate from and be resupplied, hence they would be operating at the limits of their range. As a result, the Germans concentrated primarily on their U-boat campaign in the North Atlantic.

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