The island of Borneo
is a land of primeval jungle. The coasts are
fringed with mangrove and swamp, and over nine-tenths of the interior
is covered with thick evergreen forests. In 1941 the population was
small – that of the whole island was estimated
at less than three million – and there were less than a dozen
settlements large enough to be called towns. There were few roads and
only one short railway; communication was by
the many waterways or by narrow jungle paths. Much of the
interior was unexplored, or very inadequately known. It was rich
in oil and other raw materials. The island was
partly Dutch and partly British. British Borneo lay along its northern
seaboard and comprised the two states of British North Borneo
and Sarawak, the small protected State of Brunei,
and the Crown Colony of Labuan Island. North Borneo and sarawak
were not technically British colonies, but “protectorates,” all of whom depended upon
the British for their protection and to run their foreign affairs.
British North Borneo was administered by a
chartered company of the same name. Labuan, just off shore, had been
managed in this way, but in 1941, it was administered directly
by the British from Singapore. Brunei was a
sultanate, and therefore an autonomous entity, although it was under
British protection, and the resident British administrator wielded more
practical administrative power than the sultan.
Sarawak, meanwhile, was a kingdom ruled since 1841 by the
British-born Brooke family, who were called the “White Rajahs.” Looking
for protection from pirates and other regional
powers, the Brookes were interested in a
protectorate relationship with Britain, but the
British were content to simply recognize them as an independent
country. Oil, and its importance, had yet to be discovered, and the
British were not interested. Later, In 1888, the United Kingdom finally granted protectorate status. While The rest of the island—collectively
known as Kalimantan—was under Dutch control. Of the five major islands on the Dutch
East Indies, Borneo was the primary objective for japanese because of
the great oil fields that were located in
both the British north and on the Dutch west side. Borneo occupies a position of great strategic
importance in the south-west Pacific. It lies across the main sea routes from
the north to Malaya and Sumatra on the one hand, and Celebes and Java on the other.
Strongly held, it could have been one of the main bastions in the defence of
the Malay barrier, but neither the Dutch nor the British had the necessary resources
to defend it. The available forces had to be concentrated further south for the
defence of Singapore and Java, and all that could be spared for Borneo and the
outlying Dutch islands were small detachments at important points which it was hoped
might prove a deterrent to attack. The oilfields in British Borneo lay in
two groups: one at Miri close to the northern boundary of Sarawak, and the
other Seria in the State of Brunei. The crude
oil was pumped from both fields to a refinery at Lutong on the coast, from
which loading lines ran out to sea. For defence at northern
borneo, Commander-in-Chief Far East, Sir Robert
Brooke-Popham had ordered the 2nd Battalion, 15th Punjab
Regiment, a heavy 6-inch gun battery from the Hong
Kong-Singapore Royal Artillery, and a detachment
of 35th Fortress Company (Royal Engineers) to proceed
to Kuching, unsupported by air or naval assets.
Given the area’s importance as an oil producer, he
should have done more. The only place which it was decided to hold
was Kuching, the reason for this being not only that there was a modern airfield at
this location, but that its occupation by the enemy might give access to the Dutch
airfields in Borneo, furthermore, it would also give the enemy access to Singapore. There had been a small RAF contingent
at Kuching, but this had been pulled back to Singapore several months earlier.
Brooke-Popham’s orders in case of a Japanese attack were simply to burn,
not defend, the petroleum industry infrastructure. In December 1940 a company
of 2/15th Punjab was sent to Miri for the protection of the demolition
parties. These troops were entrusted with the destruction of Miri Oil Fields.
While at Kuching was deployed a force of 6 Platoons of infantry from 2/15
Punjab Regiment. These troops were to conduct a delaying action at the Bukit
Stabar Airfield outside of Kuching. While the "White Rajah"
assembled a small army of local tribesmen into
a unit which he called the “Sarawak Rangers,”.
This force consisted of 1,515 troops who were
primarily Iban and Dyak tribesmen trained in the
art of jungle warfare. The defenders, Punjabis
as well as rangers, were under the unified
command of Lieutenant Colonel C.M. Lane as the
Sarawak Force (SARFOR). In August 1941, It was also decided
that no attempt should be made to defend British North Borneo, Brunei
or Labuan, and the Governor of North Borneo, Mr. Robert Smith, was
informed that the Volunteers and police were to be used solely for the
maintenance of internal security. The Oilfields in dutch borneo lies on the
east coast of Dutch Borneo, including both drilling and refining, was centered at two
locations. First was Tarakan Island, and Second was Balikpapan. The defenses in place to fend off
japanese attacks were inadequate at east borneo. As with the British in northern
Borneo, the Dutch had left the east side of the island only lightly
defended, planning to deny their
petroleum resources to the Japanese. The Royal Netherlands East Indies Army
KNIL, maintained its 6th Infantry Battalion at Balikpapan numbered
approximately 1,100 men, and its 7th Infantry Battalion at Tarakan, numbered
approximately 1,300 men. These units were each supported by two
field artillery batteries, and the ports were defended by coastal artillery
batteries, each of which consisted of a pair of 120mm guns and four 75mm guns.
The Dutch commanders at the two locations were Lieutenant
Colonel Cornelius van den Hoogenband at Balikpapan, and Lieutenant
Colonel Simon de Waal at Tarakan. Bandjarmasin, the Dutch administrative capital
for its part of Borneo, was effectively undefended. Lieutenant Colonel Henry
Halkema commanded a contingent of about 500 troops and no artillery. Like Tarakan
and Balikpapan, Bandjarmasin was also a center of petroleum activities, but of
less significance than the other two. Overhead, the mainstay
of the Military Aviation of the Royal Netherlands
East Indies ML-KNIL, was equipped with American-built
aircraft, such as Glenn Martin bombers, as well
as Curtis Hawk and the Brewster Buffalo, the
type that had proven so inadequate in Malaya. While
the Royal Netherlands Navy provided the submarines of
its Divisie Onderseeboten III, and a small number
of support vessels. In the west borneo, The Dutch forces had
a secreat airfield near the border of British Borneo called "Singkawang II",
which was defended by a smaller dutch garrison. On 25 November five Brewster
3-39 Buffalo fighter planes arrived for local defence followed in the beginning
of December by Martin B-10 bombers. while in Pontianak was defended
by west borneo KNIL garrison Battalion, commanded by Lieutenant Colonel Dominicus
Mars, numbering approximately 500 men. To gain control of the oilfields, to guard
the flank of their advance on Malaya and to facilitate their eventual attack on Sumatra
and western Java, the Japanese decided, as a subsidiary operation to their Malayan
campaign, to seize British Borneo. This operation was launched by Southern Army eight
days after the initial attack on Malaya. On 20 November 1941, the
Kawaguchi Brigade was activated in Tokyo, and placed
under the direct command of the Southern Army. It was
commanded by Major-General Kiyotake Kawaguchi and it
was composed mainly of the 35th Infantry Brigade and
the 124th Infantry Regiment from IJA 18th Division, and
reinforced by engineer units from the divison and
Oil Drilling unit. Also involved in the British
Borneo operations was IJN 2nd Yokosuka Naval Landing Force.
Japanese Intelligence reported that the entire
island was covered with dense jungle. there were no
roads connecting the major cities. All long-distance
transportation was by sea. For the invader, there
was no opportunity to use tanks, motor vehicles, or
that stellar conveyance of the Malay campaign, bicycles.
Each of the objectives would require a separate
amphibious assault. General Kawaguchi decided that the first
landings would be made at Miri and Seria in order to capture vital oilfields
and airfields in these towns on 16th december 1941. Part of the force would
remain in this area to reestablish Miri oilfield while the main body would advance
and capture the Kuching airfield. For the east borneo, The
Japanese battle plan called for Tarakan Island to be
invaded on January 10, with Balikpapan assaulted soon after.
In preparation, the Japanese flew a
number of reconnaissance missions, and had begun
flying bombing missions on Christmas Day. The main
objective of the invasion of Tarakan Island was the capture
of the oilfields, oil refineries and the airfield
located on the island. The invasion will go through Central
Force, commanded by Vice Admiral Ibo Takahashi. Leading the attack would be the
56th mixed infantry group AKA Sakaguchi Detachment, drawn from the IJA 56th Infantry
Group of the 56th Division, commanded by Major General Shizuo Sakaguchi,
based on the 146th Infantry Regiment, and reinforced by artillery, armored, and
engineer units drawn from the division. Whereas the northern Borneo attack had
launched from Cam Ranh Bay in Vietnam, the Sakaguchi Detachment sailed from
Davao in the Philippines, which they had captured in December as a base of
operations for the Dutch Borneo assault. Also involved in the Dutch
Borneo operations was the IJN 2nd Kure Special
Naval Landing Force, a battalion-sized
contingent of IJN ground troops under Lieutenant
Commander Masanari Siga. At 13:00 on 13 December 1941, the Japanese
invasion convoy consisted of 10 transport ships left Cam Ranh
Bay, Indo-China, escort by an IJN escort under
Rear Admiral Shintaro Hashimoto, a task force
which included the cruiser Yura, four destroyers,
and a sub-chaser. It was an imposing force, considering that
northern Borneo was virtually undefended. The convoy crossed the South China
Sea without being sighted, and at about 23:30 on the 15th, the main body
of the convoy arrived at the Miri and seria anchorage. at dawn on 16
December 1941, two landing units secured Miri and Seria with only very
little resistance. The main body of the Kawaguchi Detachment found
only about 50 members of the police unit defending Miri. They surrendred
with very little fighting. Two companies of the 2nd Yokosuka SNLF
landed on the coast near Lutong and within two and a half hours captured
the important Lutong oil refinery. Anticipating Brooke-Popham’s order
to destroy the drilling and refining facilities, Kawaguchi had arrived prepared.
He brought with him four field well drilling companies of
the Oil Drilling Section of the Kwantung Army’s 21st Field Ordnance Depot.
The petroleum infrastructure was torched on 8 December at the
first notice of the Japanese attacks from Malaya to Pearl Harbor, but the
Japanese engineers were capable of repairing and restoring the
drilling and refining equipment that had been damaged. after 17
December, the three batallion from main body of the Detachment prepared
for the next operation - the landing at Kuching. The Japanese troops
suffered only 40 casualties between 16 and 23 December, most were
drownings as a result of Japanese amphibious operations. Overhead, the
only air support for the defenders, would come from the Dutch, operating
out of bases far to the south in Dutch Borneo. The first came three
days after the invasion, on 19 December; two Dutch Dornier Do 24
flying boats from Tarakan Island sank the Japanese destroyer Shinonome
and damaged a transport ship. On 22 December, having achieved their immediate
objectives, the Japanese resumed their offensive. the main body consisted of two
battalions of the Japanese invasion force re-embarked at Miri and left for Kuching,
leaving one battalion to secure all British Borneo outside Sarawak. the covoy was escorted
by the cruiser Yura, the 3 destroyers. The convoy was sighted and
reported to Air Headquarters, Far East, by Dutch
reconnaissance aircraft on the morning of the 23rd.
At 11.40 that morning twenty-four Japanese aircraft
bombed Singkawang II airfield, so damaging the
runways that a Dutch striking force which had been ordered
to attack the convoy was unable to take off
with a bomb load. Air Headquarters of Far East,
ordered the transfer of the aircraft to palembang on
the afternoon of 24th. The Japanese convoy did not
however escape unscathed. On the evening of the 23rd
it was first attacked by Dutch submarine K-XIV, sank
two japanese ships and damaged two others, and the
following night another Dutch submarine K-XVI
torpedoed the IJN destroyer Sagiri near Kuching. The
K-XVI was herself sunk by Japanese submarine I-66 on
her way back to Soerabaja. The convoy was seen at
18:00 on the 23rd approaching the mouth of the Santubong River.
Two hours later Colonel Lane received
orders from Singapore to destroy the airfield. It was
too late to change back to mobile defence and, as
there seemed to him no point in attempting to defend
a useless airfield, he asked General Percival for
permission to withdraw as soon as possible into
Dutch north-west Borneo. While awaiting a reply Lane
concentrated his battalion at the airfield, with 18-pounder
gun and 3-inch mortar detachments covering the river
approaches, and a Punjabi gunboat platoon, working
with the Sarawak Rangers. The Japanese troops commande by Colonel
Akinosuke Oka landed at 11:00 . Although 2nd Battalion, 15th Punjab
Regiment, resisted the attack, they were soon
outnumbered and retreated to nearby airfield. By the afternoon, Kuching
town was in Japanese hands. The Japanese followed up and before dark made contact
with the airfield defences. As Christmas Day dawned, firing temporarily ceased.
A general withdrawal into Dutch
Borneo was ordered to start at dusk, but heavy firing was heard
to the north of Batu Kitang shortly after noon and, fearing that his line of retreat
would be cut, Lane decided on immediate withdrawal. Awaare of
Colonel Intention the japanese reinforced by
the 2nd Yokosuka SNLF, launched a full-scale attack. Two of the
Punjabi Companies were destroy, but the SARFOR succeded retreating to dutch border. At about
16:40 on the 25th, the Japanese troops completely secured the Kuching airfield. The
Japanese losses during this operation were about 100 killed and 100 wounded.
Following the capture of Kuching
airfield, the Detachment commander ordered Colonel Oka to secure the
strategic area around Kuching with the main force of the 124th Infantry Regiment, while
he with one infantry battalion left Kuching on the 27th and returned back to Miri. On
the same day, the japanese troops capture the tembelan island, which was the first
Dutch territorial loss in the Pacific War. The retreating SARFOR later
arrived at singkawang ii arfield on the 29th December.
The SARFOR is disbanded 2 days ealier after the
sarawak state force were release, in view of their
agreement to serve only in Sarawak. at singkawang
the british force joined with a garrison of 750 dutch troops.
Lane placed his battalion under Dutch command
for the defence of the airfield and the surrounding area.
The Japanese planned to attack the
airfield from the north, and also from the west by a
force landed on the coast. This attack was held up by
bad weather for nearly a week, but on the 24th January
five companies advanced along the road from the
Dutch border, and by the 25th had reached a village
two and a half miles north-east of the airfield.
the defenders launched an attack on the 26th which
was repulsed by Japanese. That evening a counter-attack
succeeded in turning their flank and early on the
27th the order was given to evacuate the airfield.
the remnant of british and dutch troops retreated
to Ledo, 15 miles to the southwest. Meanwhile three
Japanese companies had left Kuching in small craft
during the night of the 25th and by daybreak on the 27th
had landed at Pemangkat due west of the airfield.
Striking north-east and south and meeting with little
opposition, they quickly captured the coastal
villages and moved towards Bengkajang, thus threatening
to surround the Allied force at Ledo. The British
and Dutch troops retreated further into the jungle
southward trying to reach Sampit and Pangkalanbun,
where a Dutch airfield at Kotawaringin was located.
two days later, on 29th january, the japanese
landed and seize pontianak. On returning back to Miri on 28
December, Major-General Kawaguchi ordered Lieutenant Colonel Watanabe
to advance on the 31st by landing barges to Brunei with one infantry
battalion. On 1 January 1942, two infantry platoons commanded
by a company commander landed on Labuan Island, and capture the undefended
island. On 8 January, Kawaguchi proceeded to Jesselton and having
occupied that town and Beaufort, where he disarmed the small police unit.
Using ten small fishing boats, two infantry companies
(minus two platoons), commanded by Lieutenant Colonel Watanabe, captured
Sandakan, the seat of government of British North Borneo. On the morning of the 19th
January, the Governor Robert Smith surrendered the State and, refusing
to carry on the administration under Japanese control. This unit then captured Tawau and Lahad Datu on
the 24th and 31st respectively. The Japanese forces suffered no combat
casualties during this operations. the 16 transport vessels carrying the IJA’s
Sakaguchi Detachment and the Special Naval Landing Force depart from davao, Mindano for
attack on tarakan island on 7th january 1942. The Convoy were
escorted by the IJN cruiser Naka, 11 destroyers, 3 patrol ships, two seaplane tenders, and
a bevy of minesweepers and patrol boats under the command of Rear Admiral Shoji
Nishimura. On 10 January a Dutch Dornier Do-24K flying boat spotted a Japanese invasion
fleet. The Dutch Commander ordered the destruction of all oil fields on the island.
At sunset on 10 January 1942, the convoy reached its 1st anchorag. In the afternoon,
Tarakan Island was visible due the smoke caused by the Dutch
destruction of the oilfields and other vital installations.
By night the flames were so bright that the island
was clearly visible in the dark. At 18:00 hours on 10 January, the Wing and Left Wing
Unit boarded landing craft and started for their landing points. The assault went
forward that night as planned, with the Wing and Left Wing Unit using the fires to
navigate through the smoke and darkness. The Right Wing Unit, commanded by colonel
Kyohei yamamoto hit the shores on the east coast of Tarakan Island exactly at midnight
of 11 January, albeit not at their assigned location, followed by 2nd Kure Special
Naval Landing Force thirty minutes later. Tarakan is a large island,
comprising 177 square miles, much of it jungle or marshland. The
swampy terrain, combined with the smoke and fires, was a recipe
for confusion. The attackers encountered pockets of resistance
from KNIL troops, mainly ethnic Indonesians, and were compelled
to beat off one determined counterattack. Nevertheless, with
their superior numbers and superior firepower, Yamamoto’s troops
were able to battle their way through to the vicinity of the
main oilfield by noon on 11 January The IJN landing forces,
meanwhile, ran into tough going in the jungle and did not occupy
the Tarakan airfield until the following morning. Realizing
that his position was untenable, and knowing that his command had
essentially been sacrificed to delay the Japanese, Lieutenant
Colonel de Waal conveyed an offer to surrender. Yamamoto accepted
and advised General Sakaguchi. However, because of the general
confusion that then prevailed, and lack of adequate communications,
not all of the KNIL forces got the message. The left
wing unit, of the IJA 146th Infantry landed on Tarakan at 3:00
pm on 11 January. Their objective was to capture the coastal artillery
battery, which was manned by troops who were not yet
aware of de Waal’s surrender. While they were making their way
through deep jungle to reach the guns which dominated the
entrance to the harbor at Tarakan City, it was the turn of the IJN
not to get the message. two minesweepers made for the waters
off Tarakan City, entered within range of the coastal guns, came
under fire and were sunk. There was much rejoicing in the gun
batteries, but deep embarrassment for de Waal, who had already surrendered.
He agreed to obtain a surrender of the battery to
avoid further bloodshed, but when the artillerymen came down
to give themselves up, the Japanese tied them up and threw
them into the bay. It is estimated by the Allies that 219 men were drowned.
On the same day, the Empire of Japan declared war on
the Kingdom of the Netherlands. General Shizuo Sakaguchi came
ashore on Tarakan at midday on January 12 to supervise the mopping
up operations and to accept de Waal’s formal surrender. He remained
for 48 hours before embarking with most of his detachment for
the next objective, Balikpapan. On 22 January, the Japanese
fleet was sighted moving south by an American PBY
flying boat, and In the afternoon of 23 January, nine
Dutch Martin B-10 bombers, escorted by 20 Brewster
Buffaloes, attacked the Japanese convoy. The transport
ship Tatsugami Maru was damaged and Nana Maru sunk.
Near Balikpapan, the Dutch submarine HNLMS
K-XVIII, under Lieutenant Commander van Well Groeneveld,
attacked and sank the transport Tsuruga Maru, but
was later heavily damaged itself by depth charges
and forced to withdraw to Surabaya. Despite this, the
Japanese unit successfully landed southeast of
Balikpapan airfield on the evening of 24 January. The
assault unit landed without meeting enemy resistance
and, by dawn, had occupied the airfield. The southward
advance moved slowly as the bridges had been destroyed,
and the unit reached the northern outskirts of
Balikpapan City on the night of 25 January. The Dutch
garrison troops had been withdrawn and the Japanese
entered the city without a fight. A portion of the
Sakaguchi Detachment called the Surprise Attack Unit
proceeded up the river in camouflaged landing craft,
evaded detection, and landed just south of the reservoir
at 04:30 on the 25th. thus cutting off the Dutch
line of retreat. While the unit was advancing along
the road to Balikpapan City, it ran into a Dutch
military column, commanded by Lieutenant Colonel C.
van den Hoogenband, attempting to escape from Balikpapan.
After defeating this Dutch column, the
Surprise Attack Unit proceeded to Balikpapan City. After
Balikpapan was occupied, a new detachment was formed led by Lt.
Col. Kume. He was ordered to secure and
protect the oil fields. While the Japanese invasion force was
landing at Balikpapan, on the early morning of 24 January, at around
02:45, the 59th U.S. Navy Destroyer Division under Rear Admiral William A.
Glassford, attacked the Japanese navy escort. The U.S. Destroyer
Division composed of 4 cleson-class destroyer, along with 2 cruisers,
attacked the twelve transport ships and the three patrol boats escorting them.
The Japanese destroyer escorts meanwhile were undertaking
a search for the Dutch submarine which had been sighted earlier.
with the japanese destroyer on the submarine chased the transport were
protected mainly by 3 patrol ships. At least four transport ships—Kuretake
Maru, Nana Maru, Sumanoura Maru and Tatsukami Maru were sunk in torpedo
attacks and a patrol boat P-37 were sunk in the attack. Two other
transports were damaged by gunfire or torpedoes. with no effective
counterfire, the 4 USN destroyer escape with minimal damaged at 16:00.
Although 4 transport ships were sunk and damaged 2 other, the USN success
does not impact the japanese because the the invasion troops already
disembarked from the transport. For General Shizuo Sakaguchi, the conquest
of Balikpapan on January 26 left only Bandjarmasin at the south end of Borneo, which
was important because it was the seat of Dutch power and the only
major population center on Borneo that was not
yet under Japanese control. The area around Bandjarmasin was
strategically important to the Japanese because of the well-constructed airfields,
which would be important bases for Japanese bombers patrolling and controlling the
waterways to the south as operations were undertaken across the rest of the Dutch
East Indies. For this next step, Japanese tactics changed significantly. Largely because
Japanese naval power was being assembled for operations in Java and Sumatra, and
because the Sakaguchi Detachment had lost most of its transport ships to enemy action,
the next step would not be an amphibious operation. Rather, it would be a pincer
movement that depended mainly on an overland march across the southern
tip of Borneo. Rather than embarking most
of his entire force, Sakaguchi just sent one battalion to advance
through the mountainous jungle terrain and than steadily south towards to Bandjermasin.
this force were named the Land drive unit. On 27 January, the sea drive unit,
consisted of one infantry company under Captain Yoshibumi Okamoto left Balikpapan
aboard small boats, intending to follow the coastline all the way to
Bandjarmasin and join the land drive unit.
His Group Headquarters would not take part and would remain in
Balikpapan to assume operational command. The forces were to coordinate surprise attacks
on Bandjermasin and capture the town. The Land Drive Unit under command of Colonel
Kyohei Yamamoto left Balikpapan on the evening of 30 January and landed in Adang
Bay without opposition before daybreak on 31st January. They marched due west carrying
nine days’ worth of field rations and bicycles, which proved useless on the jungle
trails. The mountainous terrain proved to be a far greater obstacle than the handful
of KNIL troops which they encountered, and many of the Japanese soldiers came down with
malaria or other tropical diseases. By the 8th February, the sea drive unit, who moved
only at night to concealed its position had come ashore south of Bandjarmasin and
advanced overland without opposition, to the airfield. Colonel Halkema, meanwhile, had
abandoned the city with his last 75 troops, and had retreated into central Borneo, where
he was ordered defending the airfield at Kotawaringin. At 09:00 on 10 February, the
Martapoera airfield was captured by the Advance Force. By the evening of the 10th
February, with the arrival of the main force and the Sea Land Unit, Bandjermasin was
finally occupied. There was no fighting. Most of the dutch and british
troops after the battle retreted further to terrible
jungle of central borneo. Most of the these troops were
captured by the Japanese. There were however small
parties that went to fight on in the jungle, but
they were all overwhelmed and usually executed by the Japanese.
The Japanese also payed the Dajaks (native
people who were extremely violent towards the Dutch)
to search for soldiers and to kill them. The dutch also
lost most of the native soldiers due to desertion.
After 10 weeks in the jungle -covered mountains, allied
troops surrendered on 1st april 1942. The IJA, which
had soundly defeated a superior British force in
Malaya, had now secured Dutch Borneo in the space of just
30 days without a significant land battle. With the latter
victory – counterintuitively underreported in the
global media of 1942, and largely overlooked in the
history books – Japan had secured the petroleum that
would fuel its triumphant war machine indefinitely.
It takes japanes 56 days to conquer the borneo island.
Throughout the campaign, total allied casualties
amounted to 2,599 killed or wounded and 871 captured,
while Japanese losses during this period amounted to 872
battle casualties and 9 due to malaria. The Japanese
subsequently renamed the northern part as Kita Boruneo
(North Boruneo), Labuan as Maida shima (Maida Island)
and the neighbouring Dutch territories as Minami
Boruneo ( South Borneo). For the first time in modern
history all of Borneo was under a single rule. With
Borneo now secured, the Japanese now planned an advance
that placed Java and its capital Batavia, the richest
center of the Dutch Empire, as the prime target
of its southward advance.
