Borneo campaign (1945)

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Borneo campaign (1945)
Part of World War II
Borneo Campaign CMH.jpg
A map showing the progress of the Borneo campaign
Date1 May – 15 August 1945
Result Allied victory [1]

Flag of the United Kingdom.svg  United Kingdom

Flag of Australia (converted).svg  Australia
Flag of the United States (1912-1959).svg  United States
Flag of the Netherlands.svg  Netherlands

Merchant flag of Japan (1870).svg  Japan
Commanders and leaders
Flag of the United States (1912-1959).svg Douglas MacArthur [2]
Flag of Australia (converted).svg Leslie Morshead
Flag of the United States (1912-1959).svg Thomas Kinkaid
Naval ensign of the Empire of Japan.svg Michiaki Kamada
War flag of the Imperial Japanese Army (1868-1945).svg Masao Baba
35,000 15,000
Casualties and losses
2,100 casualties [3] 4,700 casualties [4]

The Borneo campaign of 1945 was the last major Allied campaign in the South West Pacific Area during World War II to liberate the-Japanese held British Borneo and Dutch Borneo. In a series of amphibious assaults between 1 May and 21 July, the Australian I Corps, under Lieutenant General Leslie Morshead, attacked Imperial Japanese forces occupying the island. Allied naval and air forces, centred on the U.S. 7th Fleet under Admiral Thomas Kinkaid, the Australian First Tactical Air Force and the U.S. Thirteenth Air Force also played important roles in the campaign. They were resisted by Imperial Japanese Navy and Army forces in southern and eastern Borneo, under Vice-Admiral Michiaki Kamada, and in the north west by the Thirty-Seventh Army, led by Lieutenant-General Masao Baba.

Borneo island

Borneo is the third-largest island in the world and the largest in Asia. At the geographic centre of Maritime Southeast Asia, in relation to major Indonesian islands, it is located north of Java, west of Sulawesi, and east of Sumatra.

Allies of World War II Grouping of the victorious countries of World War II

The Allies of World War II, called the United Nations from the 1 January 1942 declaration, were the countries that together opposed the Axis powers during the Second World War (1939–1945). The Allies promoted the alliance as a means to control German, Japanese and Italian aggression.

World War II 1939–1945 global war

World War II, also known as the Second World War, was a global war that lasted from 1939 to 1945. The vast majority of the world's countries—including all the great powers—eventually formed two opposing military alliances: the Allies and the Axis. A state of total war emerged, directly involving more than 100 million people from over 30 countries. The major participants threw their entire economic, industrial, and scientific capabilities behind the war effort, blurring the distinction between civilian and military resources. World War II was the deadliest conflict in human history, marked by 50 to 85 million fatalities, most of whom were civilians in the Soviet Union and China. It included massacres, the genocide of the Holocaust, strategic bombing, premeditated death from starvation and disease, and the only use of nuclear weapons in war.



The plans for the Allied attacks were known collectively as Operation Oboe. [5] The invasion of Borneo was the second stage of Operation Montclair, [1] which was aimed at destroying Imperial Japanese forces in, and re-occupying the Dutch East Indies, Kingdom of Sarawak, Brunei, Labuan, British North Borneo and the southern Philippines. [5] Borneo in particular was considered at the time a strategic location for its natural resource; oil and rubber. [6] The Borneo campaign was criticised in Australia at the time and in subsequent years, as pointless or a "waste" of the lives of soldiers especially following the first operation in Tarakan. [7] Modern historians such as Max Hastings have said that attacking these forces, already cut off from Japan, was a waste of resources.

Operation Montclair was a military operation during the Second World War. The final version of the outline plan originally called Operation Princeton, it outlined plans to recapture the Visayas and Mindanao in the Philippines, Borneo and the Dutch East Indies.

Dutch East Indies Dutch possession in Southeast Asia between 1810-1945

The Dutch East Indies was a Dutch colony consisting of what is now Indonesia. It was formed from the nationalised colonies of the Dutch East India Company, which came under the administration of the Dutch government in 1800.

Kingdom of Sarawak 1841-1946 kingdom on northern Borneo

The Kingdom of Sarawak was a British protectorate located in the northwestern part of the island of Borneo. It was established as an independent kingdom from a series of land concessions acquired by an Englishman, James Brooke, from the Sultanate of Brunei. The kingdom received recognition as an independent state from the United States in 1850, and from the United Kingdom in 1864.

"Any rational strategic judgment would have left them to their own devices screened by token allied forces until their nation's defeat enforced their surrender". [8]

It has been argued that the campaign did, however, achieve a number of objectives, such as increasing the isolation of significant Japanese forces occupying the main part of the Dutch East Indies, capturing major oil supplies, and freeing Allied prisoners of war, who were being held in increasingly worse conditions in the Sandakan camp and Batu Lintang camp. [9] [10] The initial Allied plan comprised six stages: Operation Oboe 1 was to be an attack on Tarakan; Oboe 2 against Balikpapan; Oboe 3 against Banjarmasin; Oboe 4 against Surabaya or Batavia (Jakarta); Oboe 5 against the eastern Netherlands East Indies; and Oboe 6 against British North Borneo (Sabah). In the end only the operations against Tarakan, Balikpapan and British Borneo—at Labuan and Brunei Bay—took place. [11] [12] The campaign opened with Oboe 1 by a landing on the small island of Tarakan, off the north east coast on 1 May 1945 using Australian built MKIII folboats. [13] Small parties paddled in the Tarakan region to obtain useful information and observe the Djoeta oilfields prior to an invasion. On 29 May 1945, The Oboe 6 party, including Sergeant J Wong Sue, was inserted into Kimanis Bay, British North Borneo for close reconnoitreing work using a Hoehn military folboat deployed from a Catalina aircraft. [13]

Sandakan camp

The Sandakan camp, also known as Sandakan POW Camp, was a prisoner-of-war camp established during World War II by the Japanese in Sandakan in the Malaysian state of Sabah. This site has gained notoriety as the Sandakan Death Marches started from here. Now, part of the former site houses the Sandakan Memorial Park.

Batu Lintang camp

Batu Lintang camp at Kuching, Sarawak on the island of Borneo was a Japanese internment camp during the Second World War. It was unusual in that it housed both Allied prisoners of war (POWs) and civilian internees. The camp, which operated from March 1942 until the liberation of the camp in September 1945, was housed in buildings that were originally British Indian Army barracks. The original area was extended by the Japanese, until it covered about 50 acres. The camp population fluctuated, due to movement of prisoners between camps in Borneo, and as a result of the deaths of the prisoners. It had a maximum population of some 3,000 prisoners.

Battle of Tarakan (1945) First stage in the Borneo campaign of 1945 during World War II

The Battle of Tarakan was the first stage in the Borneo campaign of 1945. It began with an amphibious landing by Australian forces on 1 May, code-named Operation Oboe One. While the battle ended with success for the Allied forces over the Japanese defenders, this victory is generally regarded as having not justified its costs.

On 10 June 1945, Oboe 6 subsequently followed with simultaneous assaults on the island of Labuan and the coast of Brunei in the north west of Borneo. [12] A week later, the Australians followed up with attacks on Japanese positions around Weston on the north-eastern part of Brunei Bay. [14] [15] The attention of the Allies then switched back to the central east coast, with Oboe 2. The last major amphibious assault of World War II was at Balikpapan on 1 July 1945. [16] These operations ultimately constituted the last campaigns of Australian forces in the war against Japan. [17]

Weston, Sabah Place in Sabah, Malaysia

Weston is a town on the west coast of the state of Sabah in Malaysia. It is located in the Interior Division of Sabah, and is about 100 kilometres south of Sabah's capital Kota Kinabalu. Weston is one of the towns along the Pan Borneo Highway.

Balikpapan City in Indonesia

Balikpapan is a seaport city on the east coast of the island of Borneo, in the Indonesian province of East Kalimantan. Two harbors, Semayang and Kariangau, and Sultan Aji Muhammad Sulaiman Airport are the main transportation ports to the city. Balikpapan is the industrial, transportational, commercial and financial center of Kalimantan. The city has a population of 736,806; making it the second most populous city in East Kalimantan, after Samarinda.


Battle of North Borneo battle during the Second World War between Allied and Japanese forces

The Battle of North Borneo took place during the Second World War between Allied and Japanese forces. Part of the wider Borneo campaign of the Pacific War, it was fought between 10 June and 15 August 1945 in North Borneo. The battle involved a series of amphibious landings by Australian forces on various points on the mainland around Brunei Bay and upon islands situated around the bay. Japanese opposition to the landings was sporadic initially, although as the campaign progressed a number of considerable clashes occurred and both sides suffered relatively significant casualties. Ultimately, however, the Australians were successful in seizing control of the region, although to a large extent the strategic gains that possession of North Borneo provided the Allies with were ultimately negated by the sudden conclusion of the war in August 1945.

Battle of Labuan

The Battle of Labuan was an engagement fought between Allied and Imperial Japanese forces on the island of Labuan off Borneo during June 1945. It formed part of the Australian invasion of North Borneo, and was initiated by the Allied forces as part of a plan to capture the Brunei Bay area and develop it into a base to support future offensives.

Battle of Balikpapan (1945) 1945 battle of World War II

The Battle of Balikpapan was the concluding stage of Operation Oboe. The landings took place on 1 July 1945. The Australian 7th Division, composed of the 18th, 21st and 25th Infantry Brigades, with KNIL troops, made an amphibious landing, codenamed Operation Oboe Two a few miles north of Balikpapan, on the island of Borneo. The landing had been preceded by heavy bombing and shelling by Australian and US air and naval forces. The Japanese were outnumbered and outgunned, but like the other battles of the Pacific War, many of them fought to the death.


  1. 1 2 Ooi 2010, p. 204.
  2. Dean 2018.
  3. Australian War Memorial London.
  4. Asagumo Shimbunsha 1966.
  5. 1 2 Dean 2015, p. 279.
  6. Sandler 2001, p. 180.
  7. Hastings.
  8. Hastings 2007, p. 368.
  9. Tanaka 2017, p. 27.
  10. Mikaberidze 2018, p. 27.
  11. Dennis 1995, p. 440.
  12. 1 2 Converse 2011, p. 17.
  13. 1 2 Hoehn 2011, p. 71.
  14. Australian War Memorial 1968, p. 644.
  15. Great Britain. Ministry of Defence Navy 1995, p. 175.
  16. Pfennigwerth 2009, p. 166.
  17. Long 1963, p. 49.

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