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) The Indian Ocean was the only place where German and Japanese forces fought in the same theatre. Arrangements were made to avoid incidents between U-boats and Japanese submarines - 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.
Read more about Monsun Gruppe: Indian Ocean Trade Routes, Axis Strategic Raw Materials, Joint Operations in The Indian Ocean, First Wave of Monsun Gruppe U-boats, Later Sailings From Europe, Submarine Patrols From Penang, Japanese Salvage