Operation Re

This was the Japanese attempt to seize Milne Bay near the south-eastern tip of Papua in parallel with ‘Mo’ (ii) against Port Moresby (25 August/6 September 1942).

The Battle of Milne Bay was centred on the Japanese use of naval troops of the Kaigun Rikusentai (special naval landing forces) with limited armoured support to attack the Allied airfields at Milne Bay on the eastern tip of Papua. As a result of poor intelligence work, the Japanese miscalculated the size of the predominantly Australian garrison and, believing that the airfields were held by only two or three companies, initially landed a force of about battalion strength on 25 August 1942. Warned by ‘Ultra’ intelligence, the Allies had reinforced their garrison very considerably.

Despite suffering a significant reverse early in the campaign, when part of the invasion force had its landing craft destroyed by Allied aircraft before it could land on the coast behind the Australian positions, the Japanese quickly pushed inland and began to advance on the airfields. Heavy fighting followed as the Japanese encountered the Australian militia battalions which constituted the Allied first line of defence. These troops were steadily pushed back, but the Australians then brought forward veteran regular battalions, whom the Japanese had not expected. Allied air superiority helped tip the balance, providing close support over the battlefield and crippling the Japanese logistic efforts. Finding themselves outnumbered, lacking in supplies and suffering heavy casualties, the Japanese withdrew their forces, and the fighting ended on 7 September.

The battle is considered to be the first significant battle in which Allied troops decisively defeated Japanese land forces. Although these latter had experienced local setbacks elsewhere in the Pacific earlier in the war, these actions had not forced them to withdraw completely and abandon their strategic objective, as became the case at Milne Bay.

Milne Bay is a sheltered but deep bay with an area of 97 sq miles (251.25 km²) at the eastern tip of Papua, and measures 22 miles (35.5 km) in length and 10 miles (16 km) in width. The bay is an excellent anchorage, though the approaches were beset by many reefs, a large number of them uncharted. The coastal area is flat with good aerial approaches, and therefore suitable for airstrips despite the fact that there are streams and mangrove swamps. Because much of the land is swampy and there is rainfall of about 200 in (5080 mm) per year, the area is prone to malaria and flooding. After floods, the coastal plains become quagmires of thick and glutinous mud, rendering movement all but impossible. The bay is an inlet into the Stirling mountain range, whose peaks in place rise to between 3,000 and 5,000 ft (915 and 1525 m), and which is covered in tall jagged-edge kunai grass and dense scrub. The largest area of firm ground suitable for construction and development is located at the head of the bay. In 1942 this area was occupied by plantations of palm oil, coconuts and cocoa, as well as a number of jetties and villages, connected by an earth track 33 to 39 ft (10 to 12 m) wide. The area was sparsely populated, although there were a number of villages along the track. Ahioma was the settlement located farthest to the east and Gili Gili that farthest to the west, and between these were Lilihoa, Waga Waga, Goroni, KB Mission, Rabi and Kilarbo.

After its start in December 1941 with the ‘Ai and ‘M’ (ii) attacks on the US forces at Pearl Harbor and in the Philippine islands group, and the ‘C’ (ii) and ‘E’ (i) attacks on the British forces at Hong Kong and in Malaya, the Japanese advanced to the south in the so-called ‘Concentric Offensive’, overwhelming all British in Malaya to take Singapore in February 1942, and successfully occupying the Netherlands East Indies, Timor, and Kavieng and Rabaul, the last two of these in the Bismarck islands group to the north of New Guinea. While the ‘Mo’ (ii) Japanese naval operation aimed at capturing Port Moresby was defeated in the Battle of the Coral Sea in May, elsewhere US forces in the Philippine islands group surrendered, and Japanese forces advanced toward India through Burma in ‘B’ (iii).

Although the Japanese had been defeated in the Battle of the Coral Sea, another attempt at capturing Port Moresby was anticipated and the Allied commander of the South West Pacific Area, General Douglas MacArthur, decided to establish air bases to protect Port Moresby. To the west, he authorised the construction of an air base at Merauke in the unoccupied south-eastern corner of Netherlands New Guinea. ‘Boston’ was another, authorised to the east in the largely unexplored Abau-Mullins Harbour area of south-eastern Papua on 20 May: any Japanese force approaching Port Moresby by sea would have to sail past one or other of these bases, allowing them to be detected and attacked before they reached their objective. The base in the east had other advantages: bombers flying missions to Rabaul and other Japanese bases to the north from there would not have to overfly the Owen Stanley mountain range, and would not be subject to the vagaries of the weather and air turbulence over the mountains. For that reason, an airstrip suitable for heavy bombers was desired so that they could stage there from Port Moresby and bases in northern Australia.

The commander-in-chief of the Allied Land Forces, General Sir Thomas Blamey, selected a garrison for ‘Boston’ on 24 May. The men were informed that their mission was only to defend against Japanese raids, and that in the event of a major attack they were to destroy everything of value and withdraw. The ‘Boston’ project was then put into abeyance after a reconnaissance of the area resulted in an unfavourable report. Major S. Elliott-Smith of the Australian New Guinea Administrative Unit (ANGAU) then suggested Milne Bay as a suitable alternative site, and a group of 12 Americans and Australians set out to explore Milne Bay in a Consolidated PBY Catalina flying boat on 8 June. They were impressed by the flat areas, the roads and the jetties, all of which would facilitate the construction of air bases. On receiving this party’s recommendation, MacArthur’s headquarters cancelled ‘Boston’ on 11 June and substituted Milne Bay, which received the codename ‘Fall River’.

The first troops reached Milne Bay from Port Moresby in the Dutch coasting vessels Karsik and Bontekoe, escorted by two Australian warships, the sloop Warrego and corvette Ballarat, on 25 June. Karsik berthed at a pontoon wharf made from petrol drums hastily constructed by Papuan workers recruited by the ANGAU, who also aided the unloading of the ships. The troops included 2.5 companies and a machine gun platoon of the 55th Battalion of the Australian 14th Brigade, the 9th Light Anti-Aircraft Battery with eight 40-mm Bofors guns, a platoon of the US 101st Coast Artillery Battalion (Anti-Aircraft) with eight 0.5in (12.7-mm) heavy machine guns, and two 3.7-in (94-mm) anti-aircraft guns of the 23rd Heavy Anti-Aircraft Battery. E Company of the 46th Engineers of the US Army Corps of Engineers arrived in Bontekoe with air base construction equipment.

(Some 29 ships of the Koninklijke Paketvaart-Maatschappij, with displacements of between 2,000 and 4,000 tons, had escaped to Australia after the fall of the Netherlands. These were manned by Dutch and Javanese crews, and were the lifeline of the garrison at Milne Bay, making approximately two out of every three passages there during the campaign, the remainder being by Australian, British and US ships. Five KPM ships were eventually lost during the fighting in Papua.)

Initial work on No. 1 Airstrip began on 8 June, with Papuan labourers under the supervision of ANGAU and US 96th Engineer Separate Battalion personnel clearing the designated area near Gili Gili. E Company began construction work on 30 June: in addition to the runway, they had to build camouflaged dispersal areas for 32 fighters, taxiways and accommodation for 500 men. To support the air base and the garrison, a platoon was diverted to working on the docks and roads. Although the channels in Milne Bay allowed deep-draught ships to approach within 40 ft (12 m) of the shore, they had then to be unloaded onto pontoons and the stores manhandled onto vehicles.

Three Curtiss Kittyhawk fighter-bombers of No. 76 Squadron, RAAF, landed on the airstrip on 22 July, and more aircraft of No. 76 Squadron and also No. 75 Squadron arrived on 25 July. They found that an area measuring only 4,950 by 80 ft (1,510 by 25 m) of the runway, which was 6,000 ft long and 100 ft (30.5 m) wide, was covered with perforated-steel Marsden Matting, and that there was often water over it. As a result, as they landed aircraft sprayed water about, and sometimes skidded off the runway and became bogged.

Once No. 1 Airstrip was operational, work began on two more airfields. Some 5,000 coconut trees were removed for No. 2 Airstrip, and the site was levelled and graded, but its use first required the construction of at least two 60-ft (18-m) bridges, so work shifted to No. 3 Airstrip near Kilarbo. This was constructed by the 2/43rd Engineers (less E Company), which arrived on 4 August. This was the day on which Japanese warplanes began to bomb and strafe targets in the Milne Bay area, the Japanese attacks being focused on the airfields and the engineers working on them. Four Mitsubishi A6M Reisen ‘Zero’ fighter-bomber and an Aichi D3A ‘Val’ dive-bomber attacked No. 1 Airstrip, where one Kittyhawk was destroyed on the ground, while a Kittyhawk of No. 76 Squadron shot down the dive-bomber. After this episode, the Australians established a radar system to provide early warning. On 11 August, 22 Kittyhawk aircraft intercepted 12 ‘Zero’ aircraft, but in spite of their numerical advantage, the Australians lost three Kittyhawk aircraft while claiming to have shot down four ‘Zero’ warplanes.

On 11 July, men of Brigadier John Field’s Australian 7th Brigade to arrive, usefully bolstering the Milne Bay garrison. The brigade consisted of the 9th, 25th and 61st Battalions, which were all militia units from Queensland. The brigade brought with it the guns of the 4th Battery of the 101st Anti-Tank Regiment, the 2/6th Heavy Anti-Aircraft Battery, and the 2/9th Light Anti-Aircraft Battery, along with the first Australian engineer unit, the 24th Field Company. Field assumed command of what now became Milne Force, which controlled all Allied air, land and naval forces in the area, but only when an attack was imminent. Field reported directly to Blamey’s Allied Land Forces headquarters in Brisbane rather than the New Guinea Force in Port Moresby, and his most pressing tasks were of an engineering nature. While the US engineers built the airstrips and wharves, the Australians worked on the roads and accommodation. The engineer force was so small that it had to be supplemented by infantry and Papuan labourers.

Although it was known that malaria was endemic in the Milne Bay area, anti-malaria precautions were sketchy. Men wore shorts and kept their sleeves rolled up, their mosquito-repellent cream was ineffective, quinine was in short supply, and many of the men had initially to sleep without mosquito nets, which were stowed deep in the ships’ holds and took several days to unload. A daily dosage of 10 grains of quinine was prescribed, but Field’s men were told not to take this until they had been in the area for one week, and by this time many men had been infected with the disease. Brigadier Neil H. Fairley, the director of medical services at the Allied Land Forces and an expert in the field of tropical disease, visited Port Moresby in June and became hight concerned about the ineffectiveness of the measures being taken to combat malaria, a disease which he realised could wholly destroy the entire Allied strength in Papua. He therefore ensured that the 110th Casualty Clearing Station left Brisbane for Milne Bay with a fully equipped pathological laboratory and a large quantity of anti-malarial supplies, including 200,000 quinine tablets. Unfortunately, some equipment was lost or ruined in transit, and the danger from malaria was not yet appreciated at Milne Bay.

The 55th Battalion was already badly affected by malaria and other tropical diseases, and was withdrawn to Port Moresby early in August, but the garrison was reinforced by the arrival of Brigadier George F. Wootten’s 18th Brigade of the 7th Division, which arrived between 12 and 21 August. This was a well-experienced brigade which had fought in North Africa, and comprised the 2/9th, 2/10th and 2/12th Battalions. Anti-aircraft and artillery support was provided by the 9th Battery of the 2/3rd Light Anti-Aircraft Regiment, the US 709th Anti-Aircraft Battery and the 9th Battery of the 2/5th Field Regiment, while various signals and logistics troops provided further support.

With two brigades now at Milne Bay, Major General Cyril A. Clowes was appointed to command the Milne Force, which was placed under the control of the New Guinea Force, now commanded by Lieutenant General Sydney F. Rowell, on 12 August. Clowes’s headquarters had been created in Sydney at the end of July, and was flown to Milne Bay. Clowes and some of his staff arrived on 13 August, but had to wait until the rest arrived before he could formally assume command of the Milne Force on 22 August. By this time there were 7,459 Australian and 1,365 US Army personnel (mainly a detachment of US Army engineers, in the form of the 46th Engineer Regiment) at Milne Bay, of whom about 4,500 were infantrymen. There were also about 600 RAAF personnel.

Clowes assigned the inexperienced militiamen of the 7th Brigade to the defensive role, guarding key points around Milne Bay from seaborne or airborne attack, and kept the experienced 18th Brigade in reserve as a counterattack force. Lacking accurate maps and finding that their signals equipment was unreliable in the conditions, the Australian command and control system was based largely on telephone communications or, in areas in which there was not enough line available, runners. The soft ground made movement by road and even on foot difficult.

During the second week in August, Japanese air reconnaissance had discovered the Allied presence at Milne Bay, and this was immediately appreciated as a clear threat to Japanese plan for another seaborne descent on Port Moresby. Since 18 May Japanese operations in Papua had been the responsibility of Lieutenant General Harukichi Hyakutake’s 17th Army, whose primary interest lay with the operations in the Solomon islands group. Thus Vice Admiral Gunichi Mikawa was requested to use elements of his 8th Fleet, successor to Vice Admiral Shigeyoshi Inoue’s 4th Fleet with responsibility for South-West Pacific operations since 14 July, and despite the fact that his 8th Fleet was already overextended with operations in the Solomon islands group, was already considering ways to support Major General Tomitaro Horii’s South Seas Detachment on the Kokoda Trail, between Buna and Port Moresby. Mikawa was already planning a landing on Rabi and Samarai islands the China Strait of the Louisiade islands group of Milne Bay so that a seaplane base could be built for the flank protection of the Kokoda Trail operations, and on receipt of Hyakutake’s request of 31 July for the capture of the new Allied base at Milne Bay as the 17th Army currently lacked the strength to do so. Mikawa therefore altered his core plan, replacing the capture of Samarai with the seizure of Milne Bay in ‘Re’, scheduled for the middle of August. ‘Re’ received a high priority after aircraft of the 25th Air Flotilla discovered the new Milne Bay airfields on 4 August, but was then postponed as a result of the Japanese needed to respond to the US ‘Watchtower’ landing on Guadalcanal during 7 August.

Wrongly believing that the airfields were defended by only two or three companies of Australian infantry totalling between 300 and 600 men, the initial Japanese assault force comprised only about 1,250 men. The Japanese army was unwilling to conduct the operation as it feared that any of its landing barges sent to the area would come under attack by marauding Allied warplanes and, following occasionally argumentative discussions between army and navy officers, it was agreed that the navy would assume responsibility for the landing. The assault force was therefore drawn from the Japanese naval infantry, and Commander Masajiro Hayashi’s ‘Hayashi’ Force (612 troops of Hayashi’s 5th Kure Special Naval Landing Force and 197 men of the 5th Sasebo Special Naval Landing Force led by Lieutenant Fujikawa) was scheduled to land on the east coast. The Japanese planned that another 350 men of the 10th Naval Landing Force and 100 men of the 2nd Air Advance Party would be transported by barge to land on the north coast of the peninsula at Taupota, in Goodenough Bay, and then advance across the Stirling mountains to take the the Australians from the rear. (After the battle, Vice Admiral Matome Ugaki, the chief-of-staff of the Combined Fleet, came to the conclusion that the landing element was not a high-calibre force as it contained many men aged between 30 and 35, none of them fully fit.) Naval support was to be provided by the warships of Rear Admiral Mitsaharu Matsuyama’s 18th Cruiser Division. The landing force had a useful advantage in the form of a number of light tanks, and the Japanese also had control of the sea during the night, which made it easier for their to land reinforcements and, eventually, to undertake an evacuation.

Offsetting these Japanese tactical advantages, the Allies had the strategic advantage of possessing superior intelligence about the Japanese plans. The Japanese knew very little about Allied forces at Milne Bay, while the Allies received advance warning that the Japanese were planning an invasion for, as early as the middle of July, codebreakers were able to inform MacArthur that the Japanese planned to attack Milne Bay at a time toward the end of August. The codebreakers provided detailed information about the numbers of Japanese troops which were to be landed, which units were to be committed and their standard of training, and the names of the ships which the Japanese had allocated to the operation. MacArthur’s assistant chief-of-staff for intelligence, Brigadier General Charles A. Willoughby, had anticipated a Japanese reaction against the Milne Force, and interpreted the Japanese reconnaissance on 4 August as foreshadowing an operation. After Allied naval intelligence had provided ‘Ultra’ information that the Japanese had established a submarine picket line covering the approaches to Milne Bay, Willoughby predicted that the attack was imminent, and it was in response to this that MacArthur rushed the 18th Brigade to Milne Bay. Major General George C. Kenney, commanding the US 5th AAF and the Allied Air Forces, ordered an increase in air patrols over the likely Japanese invasion routes, and also had his aircraft execute pre-emptive attacks in the Japanese airfields at Buna on 24 and 25 August, which reduced to a mere six the number of Japanese fighters available to support the attack on Milne Bay.

Despite the fact that the Japanese were on the verge of making their ‘Ka’ (ii) reinforcement landings on Guadalcanal in the Solomon islands group, thereby precipitating the Battle of the Eastern Solomons, on 23 and 24 August, aircraft of the 25th Air Flotilla carried out preparatory bombing around the airfield at Rabi.

The Japanese army was to have contributed Major General Kiyotaki Kawaguchi’s ‘Kawaguchi’ Detachment of its 17th Army as the ground force for the operation, but this had been diverted to Guadalcanal and not replaced, leaving the operation in the hands of the Japanese navy, which allocated some 850 naval infantrymen Commander Shojiro Hayashi’s 5th Kure Special Naval Landing Force, one company of the 5th Sasebo Special Naval Landing Force under the command of Lieutenant Fujikawa, the 10th Naval Landing Force and the 2nd Air Advance Party with 350 service personnel of the 16th Naval Construction Unit. So it was a wholly naval force which departed Rabaul at 07.00 on 24 August under Matsuyama’s command in two transports (8,416-ton Nankai Maru and 8,360-ton Kinai Maru) escorted by the light cruisers Tatsuta and Tenryu, destroyers Hamakaze, Oite, Tanikaze, Urakaze and Yuzuki, and submarine chasers Ch-22 and Ch-24.

At 08.30 on 24 August, Clowes’s headquarters at Milne Bay was alerted by a Lockheed Hudson bomber of the RAAF near Kitava island, off the Trobriand islands group, and coast watchers that a Japanese convoy was approaching the Milne Bay area. Escorting the transport Tasman, the Australian destroyer Arunta departed the Milne Bay area for Port Moresby after learning of an invasion force in the offing. Reports of the second Japanese convoy, comprising seven barges which had departed Buna carrying the force that would land at Taupota, were also received at this time. Once the weather had cleared, 12 Kittyhawk fighter-bombers were despatched at 12.00. The barges were spotted beached near Goodenough island, where the 350 men of the 5th Sasebo Special Naval Landing Force under Commander Tsukioka had gone ashore to rest. The Australian pilots then strafed the beached barges, and in two hours destroyed all of them and in the process stranded their former occupants.

After the initial sighting, the main invasion force of two transports supported by seven warships, remained undetected until the morning of 25 August, when it was spotted off Kitava island by a coast watcher. In an effort to intercept this force, Boeing B-17 Flying Fortress heavy bombers were despatched from bases at Mareeba and Charters Towers in Queensland, but were unable to locate their targets as bad weather intervened. Later in the afternoon of the same day, a number of Kittyhawk fighter-bombers and a single Hudson bomber attacked the convoy and attempted to attack the transports with 250-lb (112-kg) bombs near Rabi island. Only limited damage was caused to the convoy (Urakaze was slightly damaged), and no ships were sunk. As the only Allied naval presence in the area, the destroyer Arunta and transport Tasman, had been pulled back toward Port Moresby, as noted above, an RAAF tender was sent to act as a picket in the bay and thus provide early warning of the Japanese approach.

Under the distant command of Lieutenant General Sydney F. Rowell’s Australian I Corps in Port Moresby, the garrison was fully alert, and there developed a small but exceptionally bloody battle for the area.

Earlier in the day, meanwhile, Clowes had decided to shorten his lines and passed the order for D Company, 61st Battalion, which had been sent to Akioma in the east, to withdraw behind B Company at KB Mission and reposition itself at the No. 3 Airstrip at Gili Gili. A shortage of water craft, however, delayed D Company’s departure until the evening of 25 August after three luggers, Bronzewing, Elevala and Dadosee, had been requisitioned. At around 22.30, the Japanese main landing force of 1,174 men and two Type 95 Ha-Go light tanks, made landfall near Waga Waga, on the northern shore of the bay but, as a result of a navigational error in thick fog, this took place about 1.85 miles (3 km) to the east of the intended point, and therefore placed the Japanese farther from their objective. Even so, the Japanese quickly sent out patrols to secure the area, rounding up local villagers, and established a beach-head.

Later in the same evening, two of the small water craft which D Company were using for its withdrawal to Gili Gili ran into the Japanese landing force. In the firefight which resulted, Elevala was forced to beach and its occupants had to take to the jungle on foot, eventually reaching Gili Gili some time later. The other vessel, Bronzewing, was holed and 11 of its passengers were killed either in the engagement or by the Japanese after they had been captured.

By the break of day on 26 August, advancing to the west along the coast with armoured support, the Japanese had reached the main position held by B Company of the 61st Battalion around KB Mission. The Japanese moved through the jungle at the edge of the coastal track with their two tanks in the lead. Although they lacked anti-tank weapons, the Australian infantrymen were able to turn back the Japanese attack.

At this stage, the Japanese suffered a major reverse when their beach-head was heavily attacked by one Hudson and several Kittyhawk aircraft of the RAAF, and North American B-25 Mitchell and Martin B-26 Marauder medium bombers and B-17 heavy bombers of the US 5th AAF. A number of Japanese were killed by the attack, which also destroyed a large quantity of supplies and caused several landing barges to be beached and destroyed near the KB Mission. This severely degraded the Japanese supply situation, and also deprived the Japanese of the use of the landing barges to outflank the Australian defences. The Japanese had no air cover at this time as their Buna-based fighters, which were to have patrolled above Milne Bay, had been shot down by Allied fighters shortly after take-off, and Rabaul-based aircraft had been compelled to turn back by bad weather.

On land, though, the Japanese continued to advance on the 61st Battalion’s positions throughout the day. Field had tactical responsibility for the area, and decided to send two platoons of the 25th Battalion to provide support. Later, the 61st Battalion’s other two companies were also sent forward, along with their mortar platoon. The muddy nature of the track meant that the Australians could not move anti-tank guns into position, but as an interim measure sent quantities of sticky bombs and anti-tank mines to the forward units. At 16.45, with air and artillery support, the Australians launched a minor counterattack on the Japanese forward positions about 600 yards (550 m) to the east of the KB Mission, pushing the Japanese back a further 200 yards (185 m). Then, exhausted by the day’s fighting, the Australians pulled back to Motieau to the west of the KB Mission.

The Australians now tried to break contact and withdraw toward a creek line, on which they hoped to establish a defensive line as darkness descended, but the Japanese remained in close contact, harassing the Australian rearguards. B Company then sought to establish their position, while the 2/10th Battalion readied itself to move to the east in the direction of Ahioma, passing through the lines of the 25th and 61st Battalions. Early in the evening, Japanese ships shelled the Australian positions, and at 22.00 the Japanese launched a heavy attack on the Australians and maintained this sporadically through the night. By 04.00 in the morning of the following day, the Japanese had started to employ infiltration and deception techniques to try to outflank the Australian positions. Anticipating a tank attack at dawn, the Australians withdrew about 1 mile (1.6 km) to the west to reach the Gama river.

During the night, the destroyer Hamakaze had entered the bay to make contact with the Japanese troops and land supplies. The landing force had been out of radio contact since 14.00, and the destroyer was unable to raise it either by radio or with visual signalling. As a result, Hamakaze departed Milne Bay at 02.30 without landing any supplies.

Shortly after dawn, a Japanese force of eight dive-bombers escorted by 12 ‘Zero’ fighters attacked the airfield at Gili Gili. One of the attacking aircraft was shot down, and the raid inflicted only a small amount of damage. Around the KB Mission, as the Japanese meanwhile reconnoitred the Australian positions, Clowes ordered the 2/10th Battalion, of just 420 men, to move to the Gama river. This was poorly planned and seemed to possess no clear purpose as it was launched as both a reconnaissance in force and a counterattack but then developed into an attempt to establish a blocking force at the KB Mission. Moreover, while the Australians had no knowledge of the Japanese strength or intentions, and there was nothing with which to reinforce the battalion once it had moved outside the main defensive lines near the airstrips. The 2/10th Battalion’s forward patrols made contact with the 61st Battalion at around 10.30 on 27 August and, on reaching its designated position at around 17.00 began to establish itself although, in the absence of all but small numbers of entrenching tools, this was difficult. At this point the men of the 25th and 61st Battalions were ordered to pull back after losing 18 men killed, 18 men wounded and an unknown number of men missing in action.

At 20.00 the Japanese sent two Type 95 tanks, headlights blazing, into the plantation. The men of the 2/10th Battalion attempted to disable the tanks with sticky bombs, but in the prevailing humidity the bombs did not stick to the tanks. In the fighting which now followed for 2.5 hours, the Australians suffered heavy casualties. Receiving indirect fire support from the 2/5th Field Regiment’s 25-pdr gun/howitzers situated near Gili Gili, they repelled four Japanese frontal attacks. By 24.00, however, the Japanese had penetrated into the Australian position, and in the confusion the 2/10th Battalion pulled back, in some disorder, to a number of scattered positions on the western bank of the Gama river by about 02.00 on 28 August. Then another attack by Japanese tank-mounted infantry forced them back farther, passing through the 61st and 25th Battalions toward No. 3 Airstrip, which was still under construction in the area to the south of Kilarbo. During the brief engagement around the KB Mission, the 2/10th Battalion had lost 43 men killed and another 26 men wounded.

As the 2/10th Battalion withdrew, the 25th Battalion, which had moved forward from Gili Gili to relieve the 61st Battalion, deployed around the airstrip and at Rabi, Duira Creek and Kilarbo, laying mines in key locations. The airstrip in fact proved to be an excellent defensive position, for it offered wide ands clear fields of fire, while at its end, thick mud served to prevent the movement of Japanese tanks. At about the break of day, the advancing Japanese troops reached the airstrip and, covered by the fields of their field artillery and mortars, launched an attack. Although the Australians did not know it at the time, the tanks supporting the attack became stuck in the mud and were then abandoned, being discovered by an Australian patrol on 29 August. Meanwhile, men of the 25th and 61st Battalions, along with Americans of the 709th Anti-Aircraft Battery, beat back the Japanese infantry. Further strafing by Kittyhawk aircraft followed, and the Japanese were forced to fall back 1.25 miles (2 km) to the east of Rabi.

There followed a two-day lull in the fighting, and in this interval the Australians consolidated their defences. Despite the fact that it had been seriously depleted in the earlier fighting, the 6st Battalion was ordered back into the airstrip’s perimeter, subsequently deploying around Stephen’s Ridge and linking with the 25th Battalion’s positions between the coast and Wehria Creek. Fire support was provided by mortars of the 25th Battalion together with the 0.303-in (7.7-mm) Vickers heavy machine guns of the 61st Battalion and the 0.3- and 0.5-in (7.62- and 12.7-mm) Browning machine guns mounted on the US half-tracks: these engineers and anti-aircraft gunners thus became the first US troops to enter ground combat on New Guinea.

Elsewhere, the 2/12th Battalion began moving forward from Waigani with a view to delivering a counterattack. Along with the 2/9th Batalion, the 2/12th Battalion was later ordered to attack from No. 3 Airstrip to the KB Mission. Meanwhile the Japanese were also trying to regroup their forces, and Mikawa decided that the time was ripe for the reinforcement of the troops already landed. These reinforcements, in the form of 568 men of the 3rd Kure Special Naval Landing Force and 201 men of the 5th Yokosuka Special Naval Landing Force, constituted Commander Minoru Yano’s ‘Yano’ Force, which departed Rabaul on 28 August. At about 16.30 a patrolling RAAF aeroplane spotted the Japanese convoy of one light cruiser and nine destroyers, and quickly reported this to Allied headquarters. Believing that further landings were imminent, Clowes cancelled his plans for a counterattack using units of the 18th Brigade, and the 30 Kittyhawk warplanes at Gili Gili were ordered to fly to Port Moresby in case the Japanese succeeded in breaking through to the airfield. The attack did not take place, though, so at a time early in the morning on 29 August the Kittyhawk warplanes returned, reduced in numbers by the fact that two aircraft had crashed during the move.

On 29 August the Japanese submarine Ro-33 torpedoed and sank the 3,310-ton Australian transport Malaita, but was itself then sunk by Arunta.

The Japanese convoy arrived off Waga Waga at 20.15 on 29 August and began to land troops and supplies. While this was taking place the warships shelled Allied positions around Gili Gili, and by 23.30 the landing had been completed. The gunfire bombardment was not significant, however, and caused no casualties. Throughout 30 August, the Australians undertook patrol operations while the Japanese laid up in the jungle in preparation for an attack during the night of 30/31 August after the ‘Hayashi’ Force and ‘Yano’ Force had linked.

Later that night the Japanese began forming up along the track at the eastern end of No. 3 Airstrip, by the sea, and at 03.00 on 31 August began their attack. Advancing over open ground and illuminated by flares fired by the Australians, the first Japanese attack was repelled by heavy machine gun and mortar fire from 25th and 61st Battalions as well as the 46th Engineer Regiment and the artillery fire of the 2/5th Field Regiment. The Japanese tried another two banzai charges, only to meet the same fate, and the heavy Japanese casualties included Hayashi. Yano now took over in local command of the Japanese forces and led the survivors of the attack, after they had re-formed in the dead ground around Poin Creek, some 200 yards (185 m) to the north of the airstrip in an attempt to outflank the 61st Battalion’s positions on Stephen’s Ridge. After running into a platoon of Australians, who engaged them with 0.303-in (7.7-mm) Bren light machine guns, the Japanese withdrew just before dawn. The Japanese who survived this attack were shocked by the heavy firepower the Allied forces had been able to deploy, and the assault force was left in a state of disarray.

Early on 31 August, the 2/12th Battalion began to move in the direction of the KB Mission, with D Company in the lead and struggling through muddy conditions along the track, which had been turned into a quagmire by the combination of heavy rain and heavy traffic. After passing through the 61st Battalion’s position, at about 09.00 the 2/12th Battalion began its counterattack along the north coast of Milne Bay. As the Australians moved they were harassed by snipers and ambush parties. They also encountered several Japanese soldiers who tried to lure the Australians in close for attack by pretending to be dead. In response, some Australians systematically bayoneted and shot the bodies of Japanese soldiers. At 12.00 the 9th Battalion of the 7th Brigade despatched two companies to occupy some of the ground that the 2/12th Battalion had regained around No. 3 Airstrip and the KB Mission.

Achieving only slow progress in the face of great Japanese resistance, the Australians managed to reach the KB Mission late in the day. A Japanese force remained there, and the Australians attacked with fixed bayonets, killing or wounding 60 Japanese, before establishing themselves at the KB Mission. Meanwhile, the 9th Battalion’s two companies took up positions at Kilarbo and between the Gama river and Homo creek with orders to establish blocking positions to allow the 2/12th Battalion to continue its advance on the morning of the following day.

During the night, a force of some 300 Japanese who had been falling back since they had encountered the 61st Battalion on Stephen’s Ridge, reached the positions of the 2/12th and 9th Battalions around the Gama river and, in a surprise attack, the Australians inflicted heavy casualties on the Japanese: after the battle the Australians estimated that they had killed as many as 90 Japanese. The Japanese then started to use infiltration tactics in an effort to pass through the numerous listening posts established along the side of the track which formed the front of one side of the 2/12th Battalion’s position. Elsewhere, at the KB Mission, from about 20.00, harassed the Australian positions in an effort to distract the defenders and aid their own comrades trying to break through the Australian positions from the Gama river. This lasted until the break of day.

On 31 August Hyakutake had decided that ‘Re’ should be abandoned so that his 17th Army could concentrate its strength on the defeat of the US ‘Watchtower’ operation on Guadalcanal, and therefore ordered the evacuation of the units at Milne Bay. Mikawa concurred, and on 5 September ordered a withdrawal and despatched three destroyers to assist.

During the morning of 1 September, the 2/12th Battalion went on the offensive once more, while seven Kittyhawk fighter-bombers attacked the Japanese headquarters around Waga Waga. By this time, the Japanese had abandoned their intent of reaching the airfields and instead sought only to hold off the Australians long enough to be evacuated. This was not known by the Allies, who were expecting further Japanese offensive action. The 2/9th Battalion, initially with orders to join the 2/12th Battalion’s counterattack, was delayed by a day after an erroneous intelligence report from MacArthur’s headquarters warning Clowes of a renewed Japanese attack: Clowes therefore briefly adopted a more defensive posture. The attack did not occur, and on 2 September the 2/9th Battalion was moved by barge up to the KB Mission, and on the following day took over from the 2/12th Battalion in the van of the Australian advance.

With the Japanese position at Milne Bay now on the verge of collapse, on 2 September Yano radioed the headquarters of the 8th Fleet to the effect that the Japanese had ‘reached the worst possible situation. We will together calmly defend our position to the death. We pray for absolute victory for the empire and for long-lasting fortune in battle for you all.’

The terrain in this part of Milne Bay was better suited to the defence than to the attack as it was cut by many creeks which, aligned at right angles to the coast, slowed movement and obscured fields of fire. Throughout 3 September, the 2/9th Battalion met significant resistance. In one engagement in about the middle of the morning along a stream to the west of Elevada Creek, the battalion lost 34 men killed or wounded as they attempted to force their way across a creek: engaged with sustained machine gun fire, the two assault platoons withdrew back across the creek while elements of a supporting company moved to the northern flank. Launching their assault, the Australians then found that the Japanese had withdrawn, leaving about 20 of their dead.

The 2/9th Battalion then advanced another 500 yards (460 m) to reach Sanderson’s Bay before deciding to halt for the night. During the dark hours, Japanese ships again shelled the Australian positions on the northern shore of the bay, but caused no casualties.

On 4 September, the Australian resumed their advance as the 2/9th Battalion moved to the east along the coast on each side of the coastal track. After about one hour, the advance company struck a Japanese defensive position at Goroni, and the Australians attempted to outflank the position before launching an attack at 15.15. By the end of the day, the Japanese had only 50 fully fit men, all the other surviving troops being either incapacitated or able to offer only token resistance. In addition, the commanders of all the Japanese companies had been killed, and only three or four platoon leaders remained.

After the the fighting on 31 August, the Japanese forces ashore had reported the situation to their headquarters at Rabaul, which responded by laying plans to despatch the Major General Yumio Nasu’s ‘Aoba’ Detachment centred on the army’s 4th Regiment and one company of artillery, to Rabi to complete the capture of the airfield. This force was not scheduled to arrive until 11 September, however, so it was planned in the meantime to reinforce Yano’s surviving strength with 130 men of the 5th Yokosuka Special Naval Landing Force. Attempt to land these troops on 2 and 4 September failed, and by that time, as the Japanese headquarters received further reports, it became apparent that Yano’s men would not be able to survive until the ‘Aoba’ Detachment’s arrival. On 5 September, therefore, the Japanese high command ordered a withdrawal, which was carried out from the sea that evening.

Meanwhile, six Bristol Beaufort torpedo bombers of the RAAF’s No. 100 Squadron had arrived at Milne Bay on 5 September. An additional three aircraft, Bristol Beaufighter heavy fighters of the RAAF’s No. 30 Squadron, joined them the following day. The Beaufort aircraft were tasked with providing additional support against further landings and undertaking anti-shipping missions. On 6 September, the Allied offensive reached the main camp of the Japanese landing force, fighting a number of minor actions against small groups that had been left behind after the evacuation.

The destroyer Arunta and sloop Swan had been delivering reinforcements from Port Moresby at this time, and were now ordered to make every effort to disrupt if not prevent the evacuation of the Japanese land forces landed at Milne Bay by cruisers and destroyers.

Soon after 22.00 on 6 September, as the small freighter Anshun was unloading cargo, the port came under fire from the Japanese light cruiser Tenryu and destroyer Arashi, and Anshun receiving about 10 hits from the cruiser before rolling onto her side. The Japanese ships also shelled shore positions at Gili Gili and Waga Waga, and illuminated but did not fire on the hospital ship Manunda. On the following night, a Japanese cruiser and a destroyer shelled the Australian positions for 15 minutes, causing a number of casualties, before leaving the bay. This was the last act of the Battle of Milne Bay. During the Australian mopping-up operations which followed, patrols tracked down and killed a number of Japanese troops trying to move overland to Buna.

On 11 September the Australian heavy cruiser Australia, Australian light cruiser Hobart, US light cruiser Phoenix and US destroyers Bagley, Helm, Henley, Patterson and Selfridge of Rear Admiral V. A. C. Crutchley’s Task Force 44, heading to the north from Brisbane, could not intercept the Japanese destroyers Yayoi and Isokaze , which were helping to evacuate Japanese troops from the Trobriand islands group, but the former was sunk by the attacks of two US aircraft.

The 350 Japanese troops who had been stranded on Goodenough island by the destruction of their barges on 24 August were not rescued until a time late in October. An attempt to evacuate the force on 11 September ended in failure when the two destroyers assigned to this mission were attacked by USAAF aircraft, resulting in the loss of Yayoi. Further rescue attempts on 13 and 22 September were also unsuccessful, though supplies were air-dropped on Goodenough island. A submarine landed further supplies and evacuated 50 sick personnel on 3 and 13 October. As part of the preparations for the attack on Buna and Gona, the 2/12th Infantry Battalion was assigned responsibility for securing Goodenough island on 19 October, and landed on the island three days later. A series of small engagements on 23 and 24 October cost the Australian force 13 men killed and 19 wounded, and the Japanese 20 men killed and 15 wounded. The remaining Japanese were evacuated by two barges to nearby Fergusson island on the night of 24 October, and the light cruiser Tenryu rescued them two days later. After securing the island, the 2/12th Battalion began work on the construction of Vivigani airfield on its east coast.

The Allies now developed the base area at Milne Bay to support their counter-offensive along the north coast of Papua and New Guinea. The US base became Advanced Sub Base A on 21 April 1943, Advance Base A on 14 August and Base A on 15 November, and its Australian counterpart, the Milne Bay Base Sub Area, was established on 14 June 1943. Two 155-mm (6.1-in) coast-defence guns with searchlights were provided to protect the base from naval threats. New roads were built, and those already in existence were upgraded to make them passable in the wet conditions. By June 1944, there were more than 100 miles (160 km) of road in the area.

A bitumen-surfaced second runway was built at No. 1 Airstrip by No. 6 Mobile Works Squadron of the RAAF, after which the original runway was used only for emergencies and taxiing. The minefield around No. 3 Airstrip was lifted and the airstrip was completed, with revetments and hardstands for 70 medium bombers. A new wharf, known as Liles’ Wharf after the US engineer who supervised its construction, was built in September and October 1942 to handle vessels up to the size of 7,175-ton Liberty ships, so such vessels could henceforth sail direct from the USA to Milne Bay, reducing the pressure on Australian ports and saving two or three days’ sailing time as well as the time taken to unload and then reload the cargo on smaller ships. PT-boats were based at Milne Bay from December 1942, and a transhipment and staging area, overhaul facilities for PT-boats, a destroyer base and a station hospital were also constructed.

Milne Bay was used as a staging area for the ‘Postern’ landing at Lae in September 1943 and the New Britain campaign in December, and remained operational until the end of the war.

The Australians estimated Japanese casualties in the Battle of Milne Bay as about 700 to 750 killed in action, and a Japanese source reported 625 killed in action. Of the 1,943 Japanese landed at Milne Bay, ships of the 18th Cruiser Division managed to evacuate 1,318 men, including 311 wounded. The Australians suffered 373 casualties, of which 167 were killed or missing in action, and the US forces lost 14 men killed and several wounded.

While the Allied casualties during the Battle of Milne Bay were light, after the battle Milne Bay suffered an epidemic of malaria which threatened the base as greatly as had the Japanese attack. More than one man in six, including Clowes, were stricken as the incidence of malaria soared to 33 per 1,000 men per week during September and then to 82 men per thousand per week during December. This imposed a huge burden on the medical units and on supplies of anti-malarial drugs. The chief pathologist of the New Guinea Force, Lieutenant Colonel Edward Ford, went to see Blamey, who was now in personal command of the New Guinea Force, and told him that 1,000 men and a large quantity of anti-malarial supplies were urgently required at Milne Bay to avert a disaster. Blamey expedited supply shipments, and made the required personnel available. The arrival of quantities of the new drug, atebrin, allowed this replacement of quinine. The incidence of malaria dropped dramatically after December, the month in which atebrin became the official Australian prophylactic drug, and by March 1943 the crisis had passed. After this, the incidence of malaria amongst the garrison at Milne Bay was similar to other bases in Papua and New Guinea.

At the strategic level, the fighting around Milne Bay resulted in the limitation of Japanese operations in the region. The defeat at Milne Bay meant that the Japanese could not bypass the holding action which the Australians were undertaking on the Kokoda Trail. The Japanese commanders were then forced to change their regional plans, shifting their focus toward an attempt to defeat the US forces on Guadalcanal, while maintaining a smaller effort around Buna and Gona under the command of Major General Tomitaro Horii. The Japanese planned that after they had retaken Guadalcanal, they would reinforce Horii’s force and launch a stronger overland attack on the Australians around Port Moresby. Finally, the Japanese defeats in the Buna and Gona area and on Guadalcanal prevented the implementation of these plans as the Allies gained the ascendency in the region throughout late 1942 and the Japanese were forced to fall back to the northern coast of New Guinea. In the aftermath of the battle, a large amount of intelligence was also gained by the Allies, providing their planners with a better understanding of the strengths and weaknesses of the Japanese and their equipment.

The most significant result of the Battle of Milne Bay was, however, the effect that the victory had on the morale of Allied servicemen elsewhere in Asia and the Pacific, especially those on the Kokoda Trail, and British troops fighting in Burma. Although the Japanese had previously suffered minor local defeats, such as the first landing at Wake island and the Battle of the Tenaru on Guadalcanal, these actions had not resulted in complete Japanese withdrawal and the abandonment of the military campaign.

Among Australian soldiers, the victory helped to dispel some of the notions about the invincibility of the Japanese soldier which had developed in the minds of Allied soldiers following the defeats early in 1942, and which had impacted on Allied planning up to that point.