Malaya, then under British occupation, was gradually occupied by Japanese forces between 8 December 1941 and the Allied surrender at Singapore on 15 February 1942. The Japanese remained in occupation until their surrender to the Allies in 1945. The first Japanese garrison in Malaya to lay down their arms was in Penang on 2 September 1945 aboard .

Prelude

The concept of a unified East Asia took form based on an Imperial Japanese Army concept that originated with Hachirō Arita, who served as Minister for Foreign Affairs from 1936 to 1940. The Japanese Army said the new Japanese empire was an Asian equivalent of the Monroe Doctrine,Anthony Rhodes, Propaganda: The art of persuasion: World War II, pp. 252–253, 1976, Chelsea House Publishers, New York especially with the Roosevelt Corollary. The regions of Asia, it was argued, were as essential to Japan as Latin America was to the USWilliam L. O'Neill, A Democracy at War: America's Fight at Home and Abroad in World War II, p. 53

The Japanese Foreign Minister Yōsuke Matsuoka formally announced the idea of the Co-Prosperity Sphere on 1 August 1940, in a press interview,James L. McClain, Japan: A Modern History p. 470 but it had existed in other forms for many years. Leaders in Japan had long had an interest in the idea. The outbreak of World War II fighting in Europe had given the Japanese an opportunity to demand the withdrawal of support from China in the name of "Asia for Asiatics", with the European powers unable to effectively retaliate.William L. O'Neill, A Democracy at War: America's Fight at Home and Abroad in World War II, p. 62 Many of the other nations within the boundaries of the sphere were under colonial rule and elements of their population were sympathetic to Japan (as in the case of Indonesia), occupied by Japan in the early phases of the war and reformed under puppet governments, or already under Japan's control at the outset (as in the case of Manchukuo). These factors helped make the formation of the sphere while lacking any real authority or joint power, come together without much difficulty. The sphere would, according to imperial propaganda, establish a new international order seeking "co prosperity" for Asian countries which would share prosperity and peace, free from Western colonialism and domination under the umbrella of a benevolent Japan.Iriye, Akira. (1999). Pearl Harbor and the coming of the Pacific War: a Brief History with Documents and Essays, p. 6. ธิชาภัทร สมใจ(1987)

Preparation

Japanese Military Affairs Bureau Unit 82 was formed in 1939 or 1940 and based in Taiwan to bring this about. In its final planning stages, the unit was under the then-Colonel Yoshihide Hayashi. Intelligence on Malaya was gathered through a network of agents which included Japanese embassy staff; disaffected Malayans (particularly members of the Japanese established Tortoise Society); and Japanese, Korean, and Taiwanese business people and tourists. Japanese spies, which included a British intelligence officer, Captain Patrick Stanley Vaughan Heenan and Lord Sempill also provided intelligence and assistance. Heenan's intelligence enabled the Japanese to destroy much of the Allied air forces on the ground.

Prior to hostilities, Japanese intelligence officers like Iwaichi Fujiwara had established covert intelligence offices (or Kikans) that linked up with the Malay and Indian pro-independence organisations such as Kesatuan Melayu Muda in Malaya and the Indian Independence League. The Japanese gave these movements financial support in return for their members providing intelligence and later assistance in determining Allied troop movements, strengths, and dispositions prior to the invasion.New Perspectives on the Japanese Occupation in Malaya and Singapore 1941–1945, Yōji Akashi and Mako Yoshimura, NUS Press, 2008, p. 30,

By 1941 the Japanese had been engaged for four years in trying to subjugate China. They were heavily reliant on imported materials for their military forces, particularly oil from the United States.Maechling, Charles. Pearl Harbor: The First Energy War. History Today. Dec. 2000 From 1940 to 1941, the United States, the United Kingdom, and the Netherlands imposed embargoes on supplying oil and war materials to Japan. The object of the embargoes was to assist the Chinese and encourage the Japanese to halt military action in China. The Japanese considered that pulling out of China would result in a loss of face and decided instead to take military action against US, British and Dutch territories in South East Asia. The Japanese forces for the invasion were assembled in 1941 on Hainan Island and in French Indochina. The troop build-up in Indo-China and Hainan was noticed by the Allies and, when asked, the Japanese advised that it related to its operations in China.

Conquest

The occupation commenced with Imperial Japanese Army landings at Padang Pak Amat beach Kota Bharu just after midnight on 8 December 1941, triggering a ferocious battle with the British Indian Army an hour before the attack on Pearl Harbor. This battle marked the official start of the Pacific War and the start of the Japanese occupation of Malaya. Kota Bharu airport was occupied in the morning. Sungai Patani, Butterworth, and Alor Star airports were captured on 9 December 1941. Japanese soldiers landing at Kota Bharu divided into two separate forces, with one moving down the east coast towards Kuantan, and the other southwards towards the Perak River. On 11 December 1941, the Japanese started bombing Penang. Jitra and then Alor Star fell into Japanese hands on 12 December 1941. The British had to retreat to the south. On 16 December 1941, the British left Penang to the Japanese, who occupied it on 19 December.

The Japanese continued to advance southwards, capturing Ipoh on 26 December. Fierce resistance to Japanese progress in the Battle of Kampar lasted three days and three nights between 30 December 1941 and 2 January 1942, before the British had to retreat once again. On 7 January 1942, two brigades of the 11th Indian Infantry Division were defeated in the Battle of Slim River, giving the Japanese army easy passage to Kuala Lumpur, the capital of Malaya. On 9 January, the British position was becoming more desperate and the ABDACOM Supreme Commander, General Wavell, decided to withdraw all the British and Commonwealth forces south to Johor, thus abandoning Kuala Lumpur (which was captured by the Japanese on 13 January).

The British defensive line was established in north Johor, from Muar in the west, through Segamat, and then to Mersing in the east. The 45th Indian Infantry Brigade were placed along the western part of the line between Muar and Segamat. The Australian Imperial Force (AIF) were concentrated in the middle, from where they advanced north from Segamat, clashing with the advancing Japanese army at Gemas on 14 January. The 15th Division (forming the main Japanese force) arrived on 15 January and forced the Australians back to Segamat. The Japanese then proceeded west towards the inexperienced 45th Indian Brigade, easily defeating them. The Allied command directed the Australian 2/19th and 2/29th Battalions to the west; the 2/19th Battalion engaged the Japanese on 17 January 1942 to the south of Muar.

Fighting continued until 18 January, and despite efforts by the 2/19th and 2/29th Battalions, the Johor defensive line collapsed. The Allies had to retreat across the Johor Causeway to Singapore. As 31 January 1942 approached, the whole of Malaya had fallen into Japanese hands.1942: Singapore forced to surrender. On This Day

Occupation

Japanese policy Japanese policy for the administration of occupied territories was developed in February 1941 by Colonel Obata Nobuyoshi (Section Chief of Intelligence – Southern Army), and Lt Colonels Otoji Nishimura and Seijiro Tofuku of the General Staff. They set out five principles: acquisition of vital materials for national defence, restoration of law and order, self-sufficiency for the troops in the occupied territories, respect for established local organisations and customs, and no hasty discussion of future status of sovereignty. Administrative-wise, the Straits Settlements were to be placed directly under the Japanese Army, the Federated Malay States and Johor will remain as autonomous protectorates under their sultans, while the four northern states were to eventually revert to Thai rule.New Perspectives on the Japanese Occupation in Malaya and Singapore, 1941–1945, Yōji Akashi and Mako Yoshimura, NUS Press, 2008,

Once occupied Malaya was placed under the Malay Military Administration (Marai Gunsei Kumbu) of the Imperial Japanese Army. The 25th Army's chief of staff was the superintendent and its Chief of General Affairs Department Colonel Watanabe Wataru its executive officer. It was Wataru that implemented the occupation policies. He had a particularly hard-line view, treating the Chinese particularly harshly because of their support for mainland China against Japan. Malays and Indians were dealt with more moderately because of their cooperation.

Wataru strongly believed British rule had introduced a hedonistic and materialistic way of life to the indigenous people. He considered that they needed to be taught to endure hardship with physical and spiritual training and education. Wataru also believed that they must also be ready to give their lives if necessary to establish Hakkō ichiu (the whole world under one roof) and the Greater East Asia Co-Prosperity Sphere.Learning the 'seishin' , Akashi Yoji, retrieved 11 August 2016

When Wataru was replaced in March 1943 by Major-General Masuzo Fujimuro, the Japanese war position had deteriorated and they recognized that they needed the co-operation of the entire population. Gradually the more repressive policies towards the Chinese were lifted and advisory councils were formed.Syonan – light of the south 1942–1945, A History of Modern Singapore 1819–2005, C. M. Turnbull, NUS Press, 2009, p. 216, In March 1944 Colonel Hamada Hiroshi established a public reading room to engage in discussion with the Chinese community leaders and youth.

Cultural and geographic changes The Japanese sought to change the common language of Malaya to Japanese. Its initial moves were to change shop signs and street names.Linguafranca of Malaya, Syonan Times, 28 February 1942, p. 4, retrieved 31 March 2017 Penang was renamed Tōjō Island (東條島, Tōjō-tō) and Malaya renamed Malai (馬来, Marai).From Tojo-To To Syonan, Syonan Shimbun, 3 March 1942, p. 4, retrieved 31 March 2017Malaya Officially Renamed Malai, Syonan Shimbun, 10 December 1942, p. 1, retrieved 1 April 2017 The time zone was also moved to align with Japan.Tokyo Time All Over Malaya, Syonan Times, 3 March 1942, p. 1, retrieved 31 March 2017

The Japanese custom of bowing was also introduced with the populace expected to bow to Japanese soldiers on guard duty.Privilege To Bow To Sentry On Duty, Syonan Shimbun, 9 March 1942, p. 3, retrieved 31 March 2017 Malay was considered a dialect and the Japanese wanted it to be standardised with Sumatran.http://eresources.nlb.gov.sg/newspapers/Digitised/Article/syonantimes19421212-1.2.8 Malai, Sumatra Dialects To Be Standardised, Syonan Shimbun, 12 December 1942, p. 1, retrieved 1 April 2017

Propaganda