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. They were named after the monsoon winds that blow in the region. The U-boats were sent to disrupt Allied shipping and to obtain strategic raw materials from Japan and its occupied territories. The Gruppe Monsun faced many challenges, such as long distances, tropical climates, hostile waters, and limited supplies. Only a few U-boats survived the war and returned to Europe.
The division was formed in 1943, when Germany decided to send some of its U-boats to the Indian Ocean. The U-boats had to travel through the Atlantic Ocean, around the Cape of Good Hope, and into the Indian Ocean. This was a risky journey, as they had to avoid Allied patrols, air attacks, and minefields. The first U-boat to reach the Indian Ocean was U-178, which arrived in Penang, a British colony occupied by Japan, in September 1943. Penang became the main base for the Gruppe Monsun, where they could refuel, rearm, and repair.
The fleet consisted of different types of U-boats, such as Type IXD2, Type IXD1, Type IXC/40, Type IXC, and Type VIIC. Some of them were converted into transport U-boats, which carried cargo such as rubber, tin, tungsten, quinine, and opium from Japan to Germany. These U-boats were also known as "milch cows", as they supplied other U-boats with fuel and torpedoes. The Gruppe Monsun also included some Italian submarines that had joined the German side after Italy's surrender in 1943. They operated in various areas of the Indian Ocean, such as the Arabian Sea, the Bay of Bengal, the Malacca Strait, and the Java Sea. They also ventured into the Pacific Ocean, reaching as far as Australia and New Zealand. They attacked Allied merchant ships, warships, and oil tankers, sinking or damaging over 100 vessels. They also engaged in covert operations, such as landing agents and saboteurs on enemy shores, rescuing downed pilots, and delivering supplies to isolated German outposts.
The division faced many difficulties and dangers during their missions. They had to deal with tropical diseases, such as malaria and dysentery, which affected their health and morale. They also had to cope with extreme heat and humidity, which caused technical problems and corrosion on their U-boats. They had to contend with Allied naval and air forces, which intensified their patrols and attacks in the Indian Ocean. They also had to overcome communication problems with their Japanese allies, who sometimes mistook them for enemy submarines or failed to provide adequate support.
The Gruppe Monsun gradually lost its effectiveness and strength as the war progressed. Many of its U-boats were sunk or damaged by Allied forces or mines. Some of them were scuttled by their own crews to avoid capture or surrender. Some of them were interned by neutral countries, such as Turkey or Argentina. Only a few of them managed to return to Germany or France before the end of the war. The last U-boat to leave Penang was U-181, which departed in March 1945 and arrived in Bordeaux in August 1945.
Some would say the Gruppe Monsun was one of the most adventurous and daring units of the German Navy during World War II. They operated in remote and hostile waters, far from their homeland and support bases. They achieved some notable successes against Allied shipping and contributed to Germany's war effort. They also established a unique relationship with Japan and its people, who respected and admired them for their courage and endurance.