The was a

field army A field army (or numbered army or simply army) is a military formation in many armed forces, composed of two or more corps and may be subordinate to an army group. Likewise, air armies are equivalent formation within some air forces, and with ...

of the

Imperial Japanese Army The was the official ground-based armed force of the Empire of Japan from 1868 to 1945. It was controlled by the Imperial Japanese Army General Staff Office and the Ministry of the Army, both of which were nominally subordinate to the Emperor o ...

during

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...

History

The Japanese 18th Army was formed on November 9, 1942, under the

Japanese Eighth Area Army The was a field army of the Imperial Japanese Army during World War II. History The Japanese 8th Area Army was formed on November 16, 1942 under the Southern Expeditionary Army Group for the specific task of opposing landings by Allied forces i ...

of the

Southern Expeditionary Army Group ''Nanpō gun'' , image = 1938 terauchi hisaichi.jpg , image_size = 200px , caption = Japanese General Count Terauchi Hisaichi, right, commanding officer of the Southern Expeditiona ...

for the specific task of opposing landings by Allied forces in Japanese-occupied

New Guinea New Guinea (; Hiri Motu Hiri Motu, also known as Police Motu, Pidgin Motu, or just Hiri, is a language of Papua New Guinea, which is spoken in surrounding areas of Port Moresby (Capital of Papua New Guinea). It is a simplified version of ...

. Upon establishment, it was made up of three divisions: the 20th, which had been raised from men from

Kyushu is the third-largest island of Japan's five main islands and the most southerly of the four largest islands ( i.e. excluding Okinawa). In the past, it has been known as , and . The historical regional name referred to Kyushu and its surroun ...

, and the 41st and 51st Divisions formed from the

Kantō region The is a geographical area of Honshu, the largest island of Japan. In a common definition, the region includes the Greater Tokyo Area and encompasses seven prefectures: Gunma, Tochigi, Ibaraki, Saitama, Tokyo, Chiba and Kanagawa. Slight ...

New Guinea campaign

Both the 20th and 41st Divisions arrived in New Guinea safely. However, the 51st Division, including the army's commander,

Hatazō Adachi was a general in the Imperial Japanese Army during World War II. Early career Adachi was born into an impoverished family, originally descended from samurai, in Ishikawa Prefecture in 1890 (the 23rd year of the reign of Emperor Meiji, which is ...

, and his senior staff, came under Allied air attack while en route from their supply base at Rabaul to

Lae Lae () is the capital of Morobe Province and is the second-largest city in Papua New Guinea. It is located near the delta of the Markham River and at the start of the Highlands Highway, which is the main land transport corridor between the Highl ...

, in the

Battle of the Bismarck Sea The Battle of the Bismarck Sea (2–4 March 1943) took place in the South West Pacific Area (SWPA) during World War II when aircraft of the U.S. Fifth Air Force and the Royal Australian Air Force (RAAF) attacked a Japanese convoy carrying troops ...

. All eight transport ships and four destroyers were sunk with the loss of 3,664 men, and only 2,427 men of the division were rescued.

Operation Cartwheel Operation Cartwheel (1943–1944) was a major military operation for the Allies in the Pacific theatre of World War II. Cartwheel was an operation aimed at neutralising the major Japanese base at Rabaul. The operation was directed by the ...

, an Allied master plan implemented from mid-1943, progressively severed the supply lines between Rabaul and frontline Japanese forces. Key defeats included the withdrawal of the

Imperial Japanese Navy The Imperial Japanese Navy (IJN; Kyūjitai: Shinjitai: ' 'Navy of the Greater Japanese Empire', or ''Nippon Kaigun'', 'Japanese Navy') was the navy of the Empire of Japan from 1868 to 1945, when it was dissolved following Japan's surrender ...

from the

Solomon Islands campaign The Solomon Islands campaign was a major campaign of the Pacific War of World War II. The campaign began with Japanese landings and occupation of several areas in the British Solomon Islands and Bougainville, in the Territory of New Guinea, du ...

, followed by landings on New Britain, as well as

Aitape Aitape is a small town of about 18,000 people on the north coast of Papua New Guinea in the Sandaun Province. It is a coastal settlement that is almost equidistant from the provincial capitals of Wewak and Vanimo, and marks the midpoint of the ...

and Hollandia, in April 1944. Adachi's forces were badly affected by tropical diseases including

malaria Malaria is a mosquito-borne infectious disease that affects humans and other animals. Malaria causes symptoms that typically include fever, tiredness, vomiting, and headaches. In severe cases, it can cause jaundice, seizures, coma, or death. S ...

heat exhaustion Heat exhaustion is a severe form of heat illness. It is a medical emergency. Heat exhaustion is caused by the loss of water and electrolytes through sweating. The United States Department of Labor makes the following recommendation, "Heat illness ...

and

malnutrition Malnutrition occurs when an organism gets too few or too many nutrients, resulting in health problems. Specifically, it is "a deficiency, excess, or imbalance of energy, protein and other nutrients" which adversely affects the body's tissues a ...

for the remainder of the war, despite Adachi's efforts to achieve some form of self-sufficiency by planting crops and giving priority in rations to the sick. As ammunition began to run low, many of Japanese field commanders resorted to

banzai charge Banzai charge is the term that was used by the Allied forces of World War II to refer to Japanese human wave attacks and swarming staged by infantry units. This term came from the Japanese battle cry , and was shortened to banzai, specificall ...

s, rather than surrender. By the end of the war in September 1945, most of his forces had been annihilated. Of Adachi's original 140,000 men, barely 13,000 were still alive when the war ended.Williams and Nakagawa 2006, p. 59. The remnants of the Japanese 18th Army surrendered to the

Australian 6th Division The 6th Division was an infantry division of the Australian Army. It was raised briefly in 1917 during World War I, but was broken up to provide reinforcements before seeing action. It was not re-raised until the outbreak of World War II, when ...

Cape Wom Cape Wom is a cape (or small peninsula) near Wewak, Papua New Guinea, pointing into the Dogreto Bay of the Bismarck Sea. It was the location of the unconditional surrender by Lieutenant General (Lt Gen) Hatazo Adachi, Commander of the Japanese 1 ...

, by

Wewak Wewak is the capital of the East Sepik province of Papua New Guinea. It is on the northern coast of the island of New Guinea. It is the largest town between Madang and Jayapura. It is the see city (seat) of the Roman Catholic Diocese of Wewak. Hi ...

, New Guinea.Johnston 2008, p. 234. They were held on Mushu Island before being returned to Japan.

List of Commanders

Notes

References

Books

* * * * *

Journals

*{{cite journal, author=Williams, Peter D. , author2=Nakagawa, Naoko , title=The Japanese 18th Army in New Guinea , journal=Wartime , issue=36 , date=October 2006 , pages=58–63 , publisher=Australian War Memorial , location=Canberra, Australian Capital Territory , issn=1328-2727 18 Military units and formations established in 1942 Military units and formations disestablished in 1945 J