The 'Battle of Java', which was known to the Japanese as 'J', was fought between Japanese and Allied forces for the island of Java in the Netherlands East Indies (28 February/12 March 1942).

Under the overall command of General Sir Archibald Wavell’s ABDA Command (American-British-Dutch-Australian Command), the defence of Java was primarily the responsibility of the local Dutch commander, Luitenant-generaal Hein ter Poorten. The main land formations available to the ABDACOM on the island were three divisions of the Netherlands East Indies army (Generaal-majoor Wijbrandus Schilling’s 1^st Division, Generaal-majoor Pierre Antoine Cox’s 2^nd Division and Generaal-majoor Gustav Adolf Ilgen’s 3^rd Division), about 5,500 British troops under the command of Major General H. D. W. Sitwell, about 750 US troops under the command of Major General Julian Francis Barnes, and about 3,000 Australian troops under the command of Brigadier A. S. Blackburn.

Within the ABDACOM forces, the Dutch provided some 25,000 mostly Indonesian troops who were generally well armed but only poorly trained. The Dutch forces were deployed in four sub-commands: the Batavia (Jakarta) area (two regiments), north central Java (one regiment), south Java (one regiment), and east Java (one regiment).

The Japanese invasion force was the 16^th Army under the command of Lieutenant General Hitoshi Imamura with Lieutenant General Maruyama Masao’s 2^nd Division supported by 21 Type 97 medium tanks of the 2^nd Company and 4^th Company of the 2^nd Tank Regiment and the 16 Type 97 tankettes of the 2^nd Reconnaissance Regiment; Lieutenant General Yuitsu Tsuchihashi’s 48^th Division supported by 10 Type 95 light tanks of the 3^rd Company of the 4^th Tank Regiment and the 10 Type 97 medium tanks and five M3 light tanks of the 3^rd Company of the 2^nd Tank Regiment, and the 16 Type 97 tankettes of the 48^th Reconnaissance Regiment; Major General Shizuo Sakaguchi’s 'Sakaguchi' Detachment with the eight Type 97 tankettes of the 56^th Infantry Group Tankette Unit; and the 'Shoji' Detachment with 10 Type 95 light tanks of the 1^st Company of the 4^th Tank Regiment.

The Japanese forces were split into two groups: the Eastern Force, with its headquarters on Jolo island in the Sulu islands archipelago, included the 48^th Division and the 56^th Regimental Group, and the Western Force, based at Cam Ranh Bay in occupied French Indo-China, included the 2^nd Division and the 3^rd Mixed Regiment detached from the 38^th Division.

The British, Australian and US units were commanded by Sitwell. The British forces were predominantly anti-aircraft units: the 77^th Heavy Anti-Aircraft Regiment, 21^st Light Anti-aircraft Regiment and 48^th Light Anti-Aircraft Regiment. The only British armoured unit on Java was B Squadron of the 3^rd Hussars, which was equipped with Mk VI light tanks. Two British anti-aircraft regiments without guns, the 6^th Heavy Anti-Aircraft Regiment and the 35^th Light Anti-Aircraft Regiment, were equipped as infantry to defend airfields. The British also had transport and administrative units.

The Australian force, named 'Black' Force after its commander, included the 2/3^rd Machine Gun Battalion, the 2/2^nd Pioneer Battalion, one company of the Royal Australian Engineers, one platoon of the 2/1^st Headquarters Guard Battalion, about 100 reinforcements diverted while they were en route to Singapore, a handful of soldiers who had escaped from Singapore following its fall to the Japanese, two transport companies, one casualty clearing station, and one company headquarters unit. Blackburn decided to reorganise his troops as an infantry brigade. They were well equipped in terms of Bren light machine guns, light armoured cars, and trucks, but had few rifles, sub-machine guns, anti-tank rifles, mortars, grenades, radio equipment and Bren Gun Carriers. Blackburn managed to assemble a headquarters staff and three infantry battalions based on the 2/3^rd Machine Gun Battalion, the 2/2^nd Pioneer Battalion, and a mixed Reserve Group.

The only US ground forces in Java was the 2/131^st Field Artillery, which was a Texas National Guard unit, and this was also attached to 'Black' Force.

On 1 March, the Japanese landed at three points on Java. The Western Force's invasion convoy landed its men in Bantam Bay near Merak and at Eretan Wetan after having fought in the 'Battle of the Sunda Strait' just a few hours before the landings. Meanwhile, the Eastern Force's invasion convoy landed its men at Kragan after having defeated an ABDACOM naval force in the 'Battle of the Java Sea'.

After discussing the preparation of 'J' on 21 January with Admiral Ibo Takahashi, the commander of the 3^rd Fleet and inspected the 48^th Division at Manila in the Philippine islands group, Imamura on 30 January received the order to attack Java. The convoy bound for western Java comprised 56 transport ships carrying the headquarters of the 16^th Army, the 2^nd Division and 3^rd Mixed Regiment. The convoy departed Cam Ranh Bay at 10.00 on 18 February with Imamura aboard on the transport ship Ryujo Maru. The convoy escort was commanded by Rear Admiral Kenzaburo Hara.

At 23.20 on 28 February, the transport ships carrying the 'Nasu' Detachment and 'Fukushima' Detachment began to put ashore their charges at Merak at the western tip of Java close to Batavia. Ten minutes later they were joined by the other group of transport ships, that carrying the 'Sato' Detachment dropping anchor in Bantam Bay. By 02.00 on 1 March, all the Japanese ships had reached their designated positions. The Dutch Merak Coastal Detachment, comprising a section from the Kapitein F. A. M. Harterink’s 12^th Battalion, engaged the Japanese landing with machine gun fire but was quickly defeated. On this same day, the Japanese established their land headquarters in Serang. The 2^nd Division was divided into Major General Yumio Nasu’s 'Nasu' Detachment, Colonel Kyusaku Fukushima’s 'Fukushima' Detachment and Colonel Hanshichi Sato’s 'Sato' Detachment. The 'Nasu' detachment was ordered to capture Buitenzorg and thus cut the escape route from Batavia to Bandoeng. The 'Fukushima' Detachment and 'Sato' Detachment would meanwhile head for Batavia through Balaradja and Tangerang.

On 2 March, the 'Nasu' Detachment reached Rangkasbitung and continued toward Leuwiliang, 15 miles (24 km) to the west of Buitenzorg. The Australian 2/2^nd Pioneer Battalion and 2/3^rd Machine Gun Battalion were positioned along the bank of a river at Leuwiliang and put up a vigorous defence during the 'Battle of Leuwiliang'. Highly accurate salvoes from Battery D of the US 2/131^st Field Artillery, destroyed many Japanese tanks and trucks, and 'Black' Force managed to delay the Japanese advance for two full days before being forced to withdraw to Soekabumi lest it become trapped by Japanese flanking movements, and was ordered to retreat to Soekabumi. Around the same time, the 'Fukushima' Detachment and 'Sato' Detachment headed west toward Madja (Maja) and Balaradja (Balaraja). They found many of the bridges already destroyed by the retreating Dutch and were forced to find other routes; some units took the opportunity to make for Buitenzorg.

On 4 March, ter Poorten decided to withdraw his forces from Batavia and Buitenzorg to reinforce the defence of Bandoeng, and in the course of the following day’s evening the Dutch troops in Batavia surrendered to the 'Sato' Detachment. By the dawn of 6 March, the Japanese troops had attacked Buitenzorg, which was guarded by the 10^th Company of the Dutch 2^nd Regiment, the 10^th Company of the 1^st Regiment, Landstorm (militia) troops and a howitzer unit. In the morning Buitenzorg was occupied by the Japanese, a large number of Allied soldiers retreating to Bandoeng. The 'Nasu' Detachment pursued them through Tjiandjoer (Tjimahi) and entered the city on 9 March. The 'Shoji' Detachment also entered Bandoeng on the same day, arriving from the north after moving via Lembang.

Farther to the east, on 27 February the ships carrying 3^rd Mixed Regiment, under the command of Colonel Toshishige Shoji, had separated from the main convoy and on 1 March arrived off Eretan Wetan, near Soebang on the northern coast of western Java. The unit’s objectives were to capture the important Kalidjati airfield and thereby degrade the capabilities of the Allied air arm while the 2^nd Division attacked Batavia.

At dawn on 1 March, nine Brewster B-339 Buffalo single-engined fighters and three Glenn Martin twin-engined bombers of the Netherland East Indies air force, together with 12 Hawker Hurricane single-engined fighters of the RAF’s Nos 242 and 605 Squadrons, carried out attacks on the Japanese troops at Eretan Wetan. Using motor vehicles, the Japanese rapidly advanced to Soebang, and at 12.00 the Kalidjati airfield was occupied following a tenacious defence by 350 British troops. Meanwhile, other Japanese units, led by Major Masaru Egashira, bypassed the Allied defences and headed for Pamanoekan (Pamanukan), and thence to Cikampek (Tjikampek), where they were able to cut the road link between Batavia and Kalidjati.

The loss of Kalidjati airfield greatly alarmed the Dutch, who set about planning hasty and ill-prepared counterattacks. On 2 March, a Dutch armoured unit, the Mobiele Eenheid under the command of Kapitein G. J. Wulfhorst with approximately 20 armoured vehicle, and supported by the 250 men of Majoor C. G. J. Teerink’s 5^th Battalion, launched a counterattack on the 'Shoji' Detachment outside Soebang. The attempt initially went well, but in the afternoon was repulsed. The main strength of the Japanese 3^rd Air Brigade, under the command of Major General Saburo Endo, then arrived to take up residence at Kalidjati airfield and provide support for the ground forces.

By the night of 7 March, Japanese troops had arrived on the Lembang plateau, which is only 5 miles (8 km) north of Bandoeng. At 10.00 on 8 March, General-majoor Jacob J. Pesman, the commander at Stafgroep Bandoeng, met Shoji at the Isola Hotel in Lembang and surrendered.

On Java’s northern coast, farther to the east, the Eastern Force was centred on the 48^th Division from Mindanao island in the Philippine islands group. On 8 February, the 48^th Division had departed Davao under the protection of the 4^th Destroyer Squadron, and on 22 February the Japanese convoy arrived off Balikpapan in south-eastern Borneo, where it was joined by the 'Sakaguchi' Detachment. On 25 February the convoy departed Balikpapan and sailed southward to Java. On 27 February, the Japanese spotted an ABDACOM naval force under the command of Schout-bij-Nacht Karel Doorman and their 5^th Destroyer Squadron and other units of the 3^rd Fleet attacked the Allied warships in the 'Battle of the Java Sea'. After defeating the Allied force, the the Japanese proceeded to the south and at 00.15 on 1 March arrived off Kragan, a small village in eastern Java about 100 miles (160 km) to the west of Soerabaja.

The 3^rd (Motorised) Cavalry Squadron of the 1^st Cavalry Regiment, under the command of Ritmeester C. W. de Iongh, resisted the landing force, but the Dutch unit was swiftly defeated.

Meanwhile, a Dornier Do 24K twin-engined flying boat of the Dutch naval air arm’s 6^th Groep Vliegtuigen, Boeing B-17 four-engined heavy bombers of the US 7^th Bomber Group, Douglas A-24 single-engined dive-bombers of the US 27^th Bomb Group and Vickers Vildebeest single-engined torpedo-bombers of the RAF’s No. 36 Squadron worked round the clock to harass the invaders.

After come ashore, the 48^th Division was divided into Colonel Hifumi Imai’s Imai' Unit (Right Wing, Major General Koichi Abe’s Abe' Unit (Left Wing), Colonel Tohru Tanaka’s 'Tanaka' Unit (Tjepoe Raiding Unit and Lieutenant Colonel Kuro Kitamura’s 'Kitamura' Unit (Bodjonegoro Raiding Unit).

The 'Tanaka' Unit was ordered to occupy Tjepoe (Cepu) in order to secure the oilfields there, and the 'Kitamura' Unit was instructed to occupy Bodjonegoro, near Tjepoe. The two units planned a two-pronged attack on Soerabaja from the west through Lamongan and from the south through Djombang and Modjokerto. The 'Tanaka' Unit occupied Tjepoe on 2 March, while the 'Kitamura' Unit occupied Bodjonegoro on 3 March. The Japanese proceeded farther and overwhelmed the Dutch defences at the Ngawi Regency, Tjaroeban (Caruban), Ngandjoek, Kertosono, Kediri and Djombang.

At Porong, near Surabaya, the Dutch infantry of 8^th Battalion, 13^th Battalion and 3^rd Cavalry Unit, together with the US 131^st Field Artillery offered fierce resistance to the oncoming Japanese, but eventually, the Allied troops under General-majoor Gustav A. Ilgen had to retreat to the island of Madura after completing the demolition of the city’s infrastructure. On the evening of 9 March, Ilgen, commanding the Dutch forces in eastern Java, surrendered.

The 'Sakaguchi' Detachment from Balikpapan also joined the Eastern Force for the 'J' invasion and, after landing, was divided into three one-battalion units: the 'Kaneuji' Unit (2/124^th Regiment) under Major Kaneuji, the 'Yamamoto' Unit (1/124^th Regiment) under Colonel Yamamoto, and the 'Matsumoto' Unit (3/124^th Regiment) under Lieutenant Colonel Matsumoto. These units moved south with the task of occupying Tjilatjap in order to capture the harbour and block any Allied retreat to Australia. In one week, the three units advanced rapidly and overcame all Dutch resistanced in Blora, Soerakarta, Bojolali, Djokjakarta, Magelang, Salatiga, Ambarawa and Poerworedjo. The 'Kaneuji' Unit and 'Matsumoto' Unit moved through the mainland, captured Keboemen and Purwokerto, and arrived north of Tjilatjap on 8 March. The 'Yamamoto' Unit fanned out along the beach and mounted a two-pronged attack, entering Tjilatjap on 8 March. By then, however, the Dutch had withdrawn to Wangon, a small town located between Purwokerto and Tjilatjap. On the following day, Cox, commander of the Dutch Central Army District, surrendered.

By 7 March, the Allied defeat was inevitable, with Tjilatjap already in Japanese hands. Soerabaja was being evacuated, and Japanese troops were rapidly converging on Bandoeng from both the north and the west. At 09.00 on 8 March, ter Poorten announced the surrender of the Royal Netherlands East Indies army in Java. At 23.00, the Dutch radio station NIROM broadcast the last news from a temporary transmitter at Ciumbuluit. The announcer, Bert Garthoff, ended the broadcast with the words 'Wij sluiten nu. Vaarwel tot betere tijden. Leve de Koningin!' (We are closing now. Farewell till better times. Long live the Queen!)

The Dutch governor, Jonkheer Dr A. W. L. Tjarda van Starkenborgh Stachouwer and ter Poorten, together with General-majoor Jacob J. Pesman, commander of the Bandoeng District, met Imamura at Kalidjati that afternoon and agreed to the capitulation of all the troops on Java.

On 3 March, the US Navy gunboat Asheville was sunk to the south of Java by a Japanese naval squadron consisting of the heavy cruiser Maya and the destroyers Arashi and Nowaki. Only one man of her crew survived.

On 10 March, Imamura became the new governor of Java and Madura, thus becoming the highest authority in the occupied Netherlands East Indies. Imamura remained in this position for about eight months, until 11 November 1942. Imamura was subordinated to General Count Hisaichi Terauchi, commander of the Southern Expeditionary Army Group, headquartered at Saigon in French Indo-China. He was also the governor of the so-called 'Southern Territories' (Malaya, Burma, the Philippine islands group, Hong Kong, Java, Sumatra, and Borneo) and directly subordinated to the Imperial headquarters in Tokyo.

On 12 March, the senior British, Australian and US commanders were summoned to Bandoeng, where the formal instrument of surrender was signed in the presence of the Japanese commander in the Bandoeng area, Maruyama, who promised them the rights of the Geneva Convention for the protection of prisoners of war.

Immediately after this, the widely-spread Japanese troops were reorganised. The 16^th Army, comprising the 2^nd Division and 48^th Division, was ordered to hold Java, while the eastern territory (Lesser Sunda islands group, Celebes, Ambon and Netherlands New Guinea) became the responsibility of the Imperial Japanese navy. The other units were deployed to other combat areas in the Pacific or returned to Japan.

The surrender of the Dutch marked the end of the ABDACOM defence of the Dutch East Indies and the collapse of the so-called 'Malay Barrier' (or 'East Indies Barrier'). Because the Allied naval force had been destroyed, the Indian Ocean and the approach to Australia lay open to the Imperial Japanese navy.