Japanese privateers in World War II

(To Mario Veronesi)
09/10/23

The pirate and the corsair are characters as old as the history of navigation. Racing the seas and preying on ships are nothing new in either the First or Second World War.

The privateering war was mainly carried out by the Germans against the merchant traffic destined to supply the British Isles but, in the Second World War, the Japanese Navy also conducted a bitter privateering war, especially against the Anglo-American oil tankers that from the Persian Gulf and the The Indian Ocean supplied fuel to the Pacific front.

In addition to the numerous merchant ships we will talk about, cruisers also participated in this racing war Aoba e Kinugasa.

The success of German privateers in World War I attracted the attention of the Imperial Navy. Although we must point out that the Japanese ships conducted a completely different war from that conducted by the similar German ships Kriegsmarine. The Japanese conceived war operations differently. Armed merchant ships or “Tokusetsu Junyokan” they were passenger and cargo ships converted into armed merchant ships to be used to attack Allied merchant traffic.

In 1941 the Imperial Navy requisitioned two passenger and cargo shipsAikoku Maru andHokoku Maru of the Osaka Shipping Line which managed maritime voyages with South America, to convert them into armed merchant ships or AMCs, from the English Armed Merchant Cruiser, literally "armed merchant cruiser".

THEAikoku Maru (opening photo), was completed between 1938 and 1940 in the Tama Zosensho KK shipyard in Tamano on behalf of the shipping company Osaka Shosen KK, it was commissioned for the transport of passengers and various goods along the route to South America. In September 1941, she was requisitioned by the Imperial Navy, together with her twins, Hokoku Maru e Gokoku Maru, and sent to the Tamano shipyards where they were first armed with cannons, machine guns, torpedo tubes and then equipped for the transport and use of two reconnaissance seaplanes, and together with a fourth ship, the Kiyosumi Maru, were registered at the Kure Naval District and placed under the insignia of Vice Admiral Masao Okamura. In the same month, theAikoku Maru,Hokoku Maru , Kiyosumi Maru were assigned to 24th Corsair Squadron, attached to the Combined Fleet of the Imperial Navy, placed under the command of Vice Admiral Takeda Moriji (1889-1973).

In 1942-1943, theAikoku Maru (photo) was converted into a transport and functioned as a support ship for submarines, cargo ships and troop transports. In the late afternoon of November 24, 1941, theAikoku Maru andHokoku Maru they left the port of Iwakuni headed for the Marshall Islands, near the Jaluit atoll, they stocked up on fuel, food and various war materials.

On the evening of 13 December 1941 the two privateers sighted the American steamship Vincent of 6.210 GRT, left Sydney and headed towards Panama with a large load of rice on board. At the height of Pitcairn Island he was hit by 8 cannon shots and a torpedo, all of which hit. In a few moments the Vincent went down surrounded by flames.

The 9 officers and 27 sailors of the crew were rescued by theAikoku Maru. On 31 December 1941 the reconnaissanceAikoku Maru spotted an enemy merchantman, the US cargo ship troweling of 3.275 GRT, coming from San Francisco and bound for Manila in the Philippines. On the morning of January 2, the reserve reconnaissance aircraft again located the troweling south of the Society Islands, demanding its surrender after having flown over it several times. After receiving a negative response, the Japanese plane returned in the afternoon to bomb it. Hit by 4 bombs, the troweling it sank within a few minutes engulfed in flames. The survivors were picked up by the two Japanese privateers who had arrived at the site of the sinking in the meantime.

On 4 February 1942 the privateers reached the Truk archipelago, leaving the same day for the Hashirajima base. While underway, on the night of February 11, they intercepted and inspected the Soviet merchant ship Kym of 5.114 GRT On 13 February the two privateers disembarked the 76 shipwrecked survivors of the Vincent and troweling in the bay of Oita (Kyushu), to then leave for Hashirajima, reaching it the same evening.

On May 9, 1942 they intercepted and captured the Dutch tanker Genota of 7.987 GRT, sailing 480 miles south-east of Diego Suarez. Taken to a Japanese-controlled port, the tanker became the Japanese or.

Subsequently, they intercepted the English troop transport Elysia (photo) of 6.757 GRT sailing south of the Strait of Mozambique. At dawn on June 5th theElysia was attacked and four days later was sunk by the submarine I-18.

On June 17, they refueled the submarines of the Ko detachment, belonging to the 8th Submarine Flotilla. Then they moved to the waters south of Ceylon.

On 12 July, they successfully surrendered the New Zealand merchantman Hauraki of 7.113 GRT The ship will continue sailing to Japan, where it was incorporated into the Japanese fleet with the name of Hoki Maru. Following the success of the first two ships, thirteen more merchant ships were converted into armed vessels.

At the end of 1943, five of these ships were sunk, and the general staff of the Imperial Navy had six privateers converted into transports and support ships; while the last two were lost in action in 1944.

The converted ships were:

  • Class Aikoku Maru: Aikoku Maru, Hokoku Maru, Gokoku Maru
  • Class Akagi Maru: Akagi Maru, Asaka Maru, Awata Maru
  • Class Bangkok Maru: Bangkok Maru, Kinryu Maru, Saigon Maru
  • Class Kiyosumi Maru: Kiyosumi Maru, Kongo Maru, Ukishima Maru, Noshiro Maru

La Kiyosumi Maru (next photo) gained a certain notoriety, although, to be honest, the exploits of the Japanese privateer ships will remain archived in confidential Japanese and American dossiers for at least half a century. This ship, together with the others, were chosen for its great autonomy and speed, camouflaged with false towers, fake funnels, fake superstructures and fake loads, concealing, well hidden, a powerful armament like real auxiliary cruisers, equipped for the war against the Allied merchant traffic.

La Kiyosumi Maru it was completed in 1934 at the Kokusai Kisen KK shipyard in Tokyo on behalf of the shipping company Nippon Yusen KK. The ship was commissioned to be used to transport passengers and various goods along the Kobe-New York route. In September 1941, three months before the Japanese attack on Pearl Harbor and the start of the war in the Pacific, the Imperial Navy requisitioned it. The unit was registered at the Kure Naval District and placed under the insignia of Vice Admiral Masao Okamura; and in October 1941, the unit was assigned to 24th Corsair Squadron aggregated to the Combined Fleet of the Imperial Navy, and placed under the command of Vice Admiral Takeda Moriji.

THEAwata Maru it was completed in 1937 at the Kokusai Kisen KK shipyard in Tokyo on behalf of the shipping company Nippon Yusen Kaisha (NYK). The ship was commissioned to be used to transport passengers and cargo along the Yokohama-Liverpool route, calling at Hamburg. On 23 November 1941 the Imperial Navy requisitioned her and her conversion began on 25 November. Four individually mounted 4 mm guns were installed, a twin Type 140 96 mm anti-aircraft machine gun, 25 mm machine guns distributed in a quad emplacement, a twin emplacement and 13,2 single emplacements, three single 4 mm machine guns and two tubes 7,7 mm torpedo launcher. On April 553, 18, she found herself in the vicinity of the US Task Force which had approached Japan for the first time to launch the raid on Tokyo commanded by Colonel Jimmy Doolittle (1942-1896).

THEAwata Maru it was attacked, together with other units that crossed in the area, by US dive bombers and suffered minor damage from a bomb that fell a short distance away. In the following years she participated in several convoy escort missions and transported materials and men. On 22 October 1943 off the coast of Formosa, she was hit by four torpedoes launched from the submarine USS Grayback (SS-208), one of which caused a large explosion hitting the ammunition depot. 1.087 transported soldiers and 223 crew sailors died. The other ships in the convoy rescued 76 soldiers and 88 surviving crewmen.

THEAkagi Maru (following photo) was completed in 1936 at the Kokusai Kisen KK shipyard in Tokyo on behalf of the shipping company Nippon Yusen Kaisha (NYK). On 23 November 1941 the Imperial Navy chose the ship for its speed and autonomy and requisitioned it to participate in the ongoing conflict. On 25 November, work began at the Hitachi Zosen Sakurajima shipyard on the conversion into an auxiliary cruiser. Five individually mounted 5 mm (41 in) Type 152 guns, one 6 mm (76 in), 3 caliber anti-aircraft gun, and two 40 mm machine guns were installed. Two observation seaplanes were later added. The ship was equipped with everything necessary for camouflage: false towers, fake funnels, fake superstructures and loads. On 7,7 December 10 the unit was registered at the Kure Naval District and assigned a military crew.

On January 29, 1942, theAkagi Maru, together withAsaka Maru andAwata Maru, was assigned to 22nd privateer squadron aggregated to the Combined Fleet of the Imperial Navy, placed under the command of Vice Admiral Boshiro Hosogaya (1888-1964). On February 17 and 18, 1944, the Americans launched Operation Hailstone, a massive air-naval attack on Japanese installations on the Chuuk Islands in the Carolinas. L'Akagi Maru attempted to move away from the Chuuk Islands together with other units, but was attacked by planes launched from American aircraft carriers. She subjected to repeated attacks and was hit by three bombs, the last of which destroyed the engine room, immobilizing the ship. The survivors were collected by Katori, but they disappeared when this unit was also hit by the Americans. 512 passengers and 788 sailors died.

THEAsaka Maru it was completed in 1937 in the Mitsubishi shipyards on behalf of the shipping company Nippon Yusen Kaisha (NYK). The ship was commissioned as a reefer ship to transport cargo to various global destinations. On 10 April 1940 the Imperial Navy requisitioned it for the first time, to participate in the ongoing conflict, then returned it to its owners during the year. On 24 December 1940 she was again acquired by the Imperial Navy and on 26 December work began at the Yokosuka shipyards for her conversion into an auxiliary cruiser. The unit carried out several convoy escort missions. She was sunk by US Navy aircraft off Fisherman's Island on 12 October 1944.

La Saigon Maru it was completed in 1937 at the Kokusai Kisen KK shipyard in Tokyo on behalf of the shipping company Nippon Yusen Kaisha (NYK). On 23 November 1941 the Imperial Navy requisitioned her, and on 10 December she was registered at the Kure Naval District. On January 29, 1942, the Saigon Maru, Together with Bangkok Maru, was assigned to the Kure Security Division of the Kure Naval District of the Imperial Navy, placed under the command of Admiral Soemu Tojoda (1885-1957).

La Kongo Maru it was completed in 1934 at the Kokusai Kisen KK shipyard in Tokyo on behalf of the shipping company Nippon Yusen KK. The ship was commissioned to be used to transport passengers and various goods along the Kobe-New York route. In September 1941, the Kongo Maru received the armament necessary to carry out the war in the Tamano shipyards. Cannons, machine guns and torpedo tubes and then, all the equipment necessary for the transport and use of the observation aircraft. In October 1941, the Kongo Maru, Together with Kinryu Maru, were assigned to the 4th Combined Fleet of the Imperial Navy, placed under the command of Vice Admiral Shigejoshi Inoue.

La Kinryu Maru (photo) was completed in 1937 at the Kokusai Kisen KK shipyard in Tokyo on behalf of the shipping company Nippon Yusen Kaisha (NYK). On 23 November 1941 the Imperial Navy requisitioned her and her conversion began two days later. On 10 December she was registered at the Kure Naval District. On January 29, 1942, the Kinryu Maru, Together with Kongo Maru, the two ships mentioned above followed in the assignment.

THEUkishima Maru it was completed in 1936 at the Kokusai Kisen KK shipyard in Tokyo on behalf of the shipping company Nippon Yusen KK. The ship was commissioned to be used to transport passengers and various goods along the Kobe-New York route. In September 1941, the unit received all the armament to carry out the war in the Tamano shipyards. The works finished in October.

La Noshiro Maru was completed on 28 June 1934 at the Kokusai Kisen KK shipyard in Tokyo on behalf of the shipping company Nippon Yusen KK. Between May and July 1941, the Noshiro Maru received in the Yokosuka shipyards, first cannons, machine guns and torpedo tubes, and then all the equipment necessary for the transport and use of the observation aircraft. Upon completion of the work, completed on 14 October 1941, she was assigned to the Jokosuka Security Division of the Jokosuka Naval District, under the command of Vice Admiral N. Hirata.

We must also point out that at the end of 1941, the Imperial Navy requisitioned five merchant ships to be converted not into privateers, but into submarine transport ships. They were: theHeian Maru, Yasunuki Maru, Nagoya Maru, Rio de Janeiro Maru , Santos Maru, which in 1942 were all used as submarine transports. In the same year, the Hie Maru and in 1943 the Tsukushi Maru. In the 1942 the Nagoya Maru it was withdrawn and reused as a transport of materials and men; same fate happened in 1943 Hie Maru and Santos Maru, and in 1945 at Tsukushi Maru. While, as many as 19 other auxiliary ships were transformed into aircraft transport ships and seaplanes “Tokusetsu Suijōki-Bokan”. Of these one was from the class Tsurumi, four cargo ships of the Mercantile Steamship Co.Ltd. (OSK Lines), class Kamikawa Maru: Kamikawa Maru, Kiyokawa Maru, Kimikawa Maru, Kunikawa Maru, Hirokawa Maru. One of the class Sanyo Maru, one of the class notorious, two of the class Kashii Maru, namely the Kinugasa, and the Kagu Maru; one of the class Kamoi and two of the class Sakito Maru, Sanuki and the Sagara Maru. They each carried between 12 and 18 aircraft. While the remaining seven of the class Chitose they were transformed into real aircraft carriers, each with an air force comprising between 20 and 30 aircraft.

Photo: web