This was the US seizure of New Georgia island in the central part of the Solomon islands group, and otherwise known as ‘Operation A’ (21 June/6 October 1943).
The undertaking was the second stage in the Solomon islands campaign undertaken as the ‘Cartwheel’ element of the overall ‘Elkton’ plan by Admiral William F. Halsey’s South Pacific Area command, and was designed to coincide with the ‘Postern’ operation against Salamaua and Lae in New Guinea by the forces of General Douglas MacArthur’s South-West Pacific Area command as the two-pronged US offensive closed in on General Hitoshi Imamura’s 8th Area Army on New Britain and New Ireland.
New Georgia is an island located at about the mid-point of the Solomon islands chain. With a length of some 45 miles (72.5 km) along its primary south-east/north-west axis and an area of 786 sq miles (2037 km²), it is the largest island of the New Georgia group, which also includes Kolombangara, Rendova and Vella Lavella. New Georgia’s north coast is protected by an almost continuous coral reef, but there are passes through the southern reef into the Blanche Channel, a very deep but well-protected body of water. Blanche Bay itself is accessible only from the south-east, its narrow south-western and north-western entrances being blocked by reefs and islets. There are good anchorages on the north-west coast, facing Kolombangara across the Kula Gulf, at Bairoko Harbour, Enogai Inlet and Rice Anchorage. There are also anchorages on the south-east coast at Segi Point and Viru Harbour, and another in the form of Wickham Anchorage on the south-east coast of Vangunu island, just to the south-east of New Georgia’s southern tip. However, the best natural anchorage in the group is that at Rendova Harbour, to the north-west of the island.
The terrain of New Georgia is for the most part rugged, with jungle-clad hills. The climate is still hotter and more humid than that of Guadalcanal, and malaria is rampant.
On the outbreak of the Pacific War of World War II, the only western settlement was the Lambeti copra plantation at Munda Point, across from Rendova, where there was also a methodist mission. The local population was on good terms with the British and sided with the Allies during the war. The island possessed no transport network more sophisticated than local trails, and most travel between the various settlements was undertaken by boat or canoe. The British administration was based on Gizo island to the south-west of Kolombangara, and this had been selected for its comparatively healthy climate and low incidence of malaria.
The Japanese had first reconnoitred New Georgia island in October 1942 as they looked for the locations at which to build airfields in the area to the south-east of Rabaul to support the defence of Tulagi and Guadalcanal. A landing force of two Japanese army infantry companies and two anti-aircraft battalions arrived at Munda Point on the south-western end of New Georgia’s wider northern end on 13 November, and Japanese patrols moved to Rendova, Vangunu, Kolombangara and other islands, informing the local population that they were now under the authority of the Japanese empire.
Japanese navy construction troops landed on 21 November and started work on an airfield at Munda. This development was reported by coastwatchers, prompting the Allies to undertake photo-reconnaissance flights over the location, but these at first detected no evidence of construction. This changed in the coming weeks as the construction work was finally detected despite its camouflage. Allied aircraft then bombed the site, but the Japanese had completed the 4,700-ft (1435-m) runway by 17 December. At about that time the Japanese began construction of another airfield at Vila on the southern end of Kolombangara island, just to the north-west of New Georgia island. No Japanese air units were based at Munda, which was instead operated as refuelling station for aircraft flying from the Rabaul area to attack Guadalcanal and Tulagi islands, and later the Russell islands group.
US attacks were numerous, but the Japanese kept the airfields operational in hopes of using them as staging bases for the reconquest of the south-eastern end of the Solomon islands chain. Conversely, the Allies planned to use New Georgia as a stepping stone to isolate Rabaul and move into the north-western part of the Solomon islands chain, but it was appreciated at an early stage that with the numbers and types of amphibious craft available in 1943, Munda was an impossible initial target, so the landing would have to be made some distance away and then pave the way to a difficult advance on the Munda area through terrain which was physically very difficult and climatically very taxing.
As it became clear at the end of 1942 that their forces could not hold Guadalcanal, the Japanese commanders came to the conclusion that the Allies would move toward the Japanese main base area at Rabaul on New Britain island, and that the central islands of the Solomons group were logical rungs on this ladder to the north-west. The Imperial Japanese army believed that the attempt to hold the central part of the Solomon islands chain would ultimately be impossible, and therefore that it would be better to wait for an Allied attack on Bougainville island, whose defence would be much less costly to construct, supply and reinforce. The Imperial Japanese navy, on the other hand, preferred to delay the Allied advance for as long as possible by maintaining a distant line of defence. Given that there was no Japanese effective central command structure, the two Japanese services implemented their own plans: the navy assumed responsibility for the defence of the central part of the Solomon islands chain and the army for its northern part.
Early in 1943, Japanese defences were prepared against possible Allied landings on New Georgia, Kolombangara and Santa Isabel islands, the last on the other side of 'The Slot' to the north-east of New Georgia island. By June 1943, therefore, the Japanese had some 10,500 troops on New Georgia and 9,000 troops, based on the 13th Regiment, on Kolombangara all under the command of Major General Minoru Sasaki’s South-East Detachment headquartered at Vila. These troops were well entrenched and awaiting an Allied attack.
The retention of the New Georgia islands group had been entrusted on 31 May to the South-East Detachment, which comprised the 8th Combined Special Naval Landing Force and elements of Lieutenant General Tadayoshi Sano’s 38th Division, whose infantry group was commanded by Sasaki with the joint army and navy forces organised to the lowest echelons and defending remote landing sites. The forces based on New Georgia included the navy’s 6th Kure Special Naval Landing Force and the army’s 229th Regiment. The South-East Detachment was administratively subordinate to Lieutenant General Harukichi Hyakutake’s 17th Army, with its headquarters at Rabaul, and was operationally subordinate to Vice Admiral Baron Tomoshige Samejima’s 8th Fleet. The Japanese army and navy units on New Georgia and Kolombangara islands were reinforced with field artillery, anti-aircraft artillery and engineer units, joint detachments being deployed to Viru Harbour and Wickham Anchorage on the south-eastern end of New Georgia island, and to Rendova Harbour on the northern end of Rendova island and the villages of Kaeruka and Vura on the south-east coast of Vangunu island.
Before the end of the Guadalcanal campaign the Japanese navy established a seaplane base, defended by the 7th Combined Special Naval Landing Force and a battalion of the Japanese army (3,100 troops) at Rekata Bay, on the north coast of Santa Isabel island near its north-western end, and based here a force of patrol seaplanes to keep ‘The Slot’ and Guadalcanal island under surveillance. This base was evacuated late in September 1943 before the fall of Vella Lavella island.
Between February and May 1943, therefore, the Japanese had reinforced the New Georgia sector with a joint army and navy force, to which the two services made equal contributions to create a strength of 10,500 men. Rear Admiral Minoru Ota’s 8th Combined Special Naval Landing Force comprised the Kure 6th Special Naval Landing Force and Yokosuka 7th Special Naval Landing Force: the latter arrived on 23 February with almost 2,000 men to garrison Kolombangara, and the former established defences with more than 2,000 troops on New Georgia on 9 March around Munda and at Bairoko Harbour and Enogai Inlet on the island’s west coast to the north of Munda. A battalion of Lieutenant General Hidemitsu Nakano’s 51st Division also garrisoned Kolombangara in February, but was relieved by the 2/45th Regiment of Lieutenant General Tsutomi Akinaga’s 6th Division at a time late in April, and the 229th Regiment of Sano’s 38th Division reinforced the Munda garrison, which also included the 10th Independent Mountain Artillery Regiment and the 15th Air Defence Unit.
The Japanese expected that the first Allied objective would be Kolombangara, and that they would then land near Munda on New Georgia’s north-west coast and attack the airfield to the south. On Kolombangara the Japanese were concentrated in the area of Vila, the island’s largest town on the south-eastern part of the coast and, as noted above, had built an airfield there.
By a time late in 1942, some Allied leaders had wanted to focus on the direct capture of Rabaul, but Japanese strength there and lack of landing craft meant that such an operation could not been deemed practical in 1943. Instead, on the initiative of the US Joint Chiefs-of-Staff, a plan known as 'Cartwheel' was developed, and this proposed instead the envelopment and thus the isolation of Rabaul, thereby removing all need to take it, by simultaneous offensives to the west in New Guinea and to the north along the Solomon islands group.
The Allied base on Guadalcanal island continued to suffer from Japanese bombing raids even after the island had been declared secure on 9 February. The Japanese possession of the airfield at Munda made these raids easier by giving Japanese warplanes a convenient place at which to refuel on their way to and from their main base at Rabaul. The Allies attempted to neutralise Munda with a programme of bombing and naval shelling, but the Japanese were able to repair the airfield in short order after each attack. The Allied command therefore decided that Munda must be taken by ground troops. Since the New Georgia islands group lay within the South Pacific Area’s region of responsibility, the operation was to be undertaken under the supervision of Halsey, whose South Pacific Area command had its headquarters at Nouméa on the island of New Caledonia.
The Allied planning for 'Toenails' started in January 1943, and the invasion received formal approval from the Joint Chiefs-of-Staff on 29 March. Rear Admiral Admiral Richmond K. Turner, commanding the 3rd Amphibious Force, planned to seize four points on 30 June: Wickham Anchorage on Vangunu just to the south-east of New Georgia, Segi Point on the south-eastern tip of New Georgia, Viru Harbour a short distance to the north-west of Segi Point, and Rendova island to the south-south-east of Munda Point. A fighter airstrip for the local provision of air cover was to be constructed rapidly at Segi, a forward base and positions for heavy artillery were to be created on Rendova opposite Munda Point, and Wickham Anchorage and Viru Harbor were to serve as staging points for small craft supporting the build-up on Rendova. The US forces would then effect their main landing operation near Munda at a time and manner of their own choosing, though the expectation was that these would take place on about D+4. At about the same time, a small force would be landed near Enogai Inlet to advance to the south-west and sever the Japanese line of supply from Kolombangara at Bairoko. The main landing force was built on Major General John H. Hester’s 43rd Division, the 9th Marine Defense Battalion, and two Marine Raider battalions, with Major General Robert S. Beightler’s 37th Division in reserve at five-day notice.
An important innovation in 'Toenails' was the designation of Brigadier General Francis P. Mulcahy as the commander of the New Georgia Air Force, which was placed under Turner’s overall command. Mulcahy was to take control of all aircraft launched from Guadalcanal and the Russell islands group to support the 'Toenails' landings, and then command the air squadrons based at Segi Point and Munda once these airfields had become operational in US hands.
Lying between Guadalcanal and the New Georgia group, the Russell island groups had served as a staging base for the Japanese during the Guadalcanal campaign, and Halsey, whose South Pacific Force was redesignated as the US 3rd Fleet on 15 March 1943, decided to capture it in preparation for 'Toenails'. Early in February, therefore, he instructed Turner, formerly his deputy commander and now his Commander Amphibious Force, to undertake 'Cleanslate'.
Beginning on 21 February, Turner landed some 9,000 men of Hester’s 43rd Division and Lieutenant Colonel Harry B. Liversedge’s 3rd Marine Raider Battalion on the Russell islands group. The landings were totally unopposed because, unknown to the Allies, the Japanese had evacuated the islands soon after the completion of their 'Ke' (i) evacuation of Guadalcanal, as being superfluous to their requirements.
Alarmed that the Allies were clearly working their way up the islands of the Solomons chain, the Japanese bombed the new US base in the Russell islands group and began to strengthen their own airfields at Munda and at nearby Vila on Kolombangara island. In their turn, and as noted above, the Americans continued their attempts to batter Munda airfield into impotence with naval gunfire bombardments of doubtful utility. During the course of one of these overnight bombardment sorties, on the night of 6/7 March Rear Admiral Aaron S. Merrill’s US Task Force 68 (the light cruisers Montpelier, Cleveland and Denver, and destroyers Conway, Cony and Waller) encountered the Japanese destroyers Murasame and Minegumo as the latter were returning up Kula Gulf from delivering food and supplies to the garrison at Vila. In the ensuing action, known as the Battle of Blackett Strait, both Japanese destroyers were sunk.
The US forces next attempted to interdict the Japanese maritime lines of supply by mining the ocean approaches to Vila and Munda. This proved as ineffective as the gunfire bombardments had been, since the Japanese were able to sweep the mines without difficulty. However, on 7 May the US minelayers Gamble, Breese and Preble laid a mine barrage across the Blackett Strait, between Kolombangara and the small island of Gizo to Kolombangara’s west, in an attempt to interdict Japanese ship movements through the strait. On the following day, the Japanese destroyers Oyashio, Kagero and Kuroshio all hit mines in that area: Kuroshio sank immediately, and Kagero and Oyashio succumbed later on the same day after being attacked and further damaged by US aircraft from Henderson Field on Guadalcanal.
During the entire New Georgia campaign, it should be noted, the determination and resourcefulness of the British commonwealth coastwatchers were invaluable Allied assets. District Officer Donald G. Kennedy, a New Zealander, ensured at every village and settlement received a message stating that the islands were British, and that the British would not abandon the local population to the mercies of the Japanese. In the event, it was the prospect of Kennedy being killed or captured which persuaded Turner to advance the first Allied landings by nine days.
Before the main landings, Major General Clayton B. Vogel, the commander of the I Marine Amphibious Corps, despatched four teams, each comprising 12 Marine Raiders, to undertake reconnaissances of the New Georgia group. The men arrived off Segi Point by Consolidated PBY flying boat on 17 March and after coming ashore linked with Kennedy, who provided them with local scouts. The Marine Raiders carefully reconnoitred the islands and returned to Segi Point on 9 April with abundant intelligence. By this time, however, Kennedy’s guerrilla campaign had irritated the Japanese so acutely that they had despatched an infantry company to hunt him down, and Turner felt compelled to send two companies of the 4th Marine Raider Battalion on an extemporised mission to Segi Point to reinforce Kennedy. Part of Lieutenant Colonel Michael D. Currin’s 4th Marine Raider Battalion arrived at 05.50 on 20 June in two destroyer transports which braved the poorly charted passage to Segi Point, then slipped back out to return to Guadalcanal. Then two more destroyer transports of the Eastern Landing Force arrived on the following day with one company of the 1/103rd Infantry and naval surveying specialists, under the command of Colonel Daniel H. Hundley, to begin laying out the airstrip.
The Allies had planned to launch their invasion of New Georgia island in the middle of April 1943, but the need to build airfields on the Russell, Woodlark and Kiriwina island groups for support of ‘Toenails’, together with the assembly of the required forces and all their equipment and supplies, delayed the start to a time late in June. Although his command was part of Admiral Chester W. Nimitz’s Pacific Ocean Areas command, Halsey was operationally controlled by MacArthur, and ‘Toenails’ was planned as a stepping stone toward Bougainville island at the north-western end of the Solomon islands group, so the airfield at Munda was of major importance as the location which could be used for the land-based air support of operations farther up the Solomon islands chain.
So far as the Americans were concerned, the primary problem for the planning was the fact that the New Georgia group is a complex of close-lying islands surrounded by shallow water and reefs so, as indicated above, Halsey’s staff came immediately to the conclusion that the assault would need first to take two outlying islands (Rendova as an artillery fire support base for the following assault on Munda, and Vangunu so that an advanced floating base at Wickham Anchorage could be protected) as well as the anchorage at Viru Harbour as a supply point, and Segi Point as a fighter airstrip. US possession of these places would allow the definitive attack to close on Munda indirectly as no heavy ships could get within gunfire bombardment range.
As noted above, the Japanese defence numbered some 10,500 men scattered to defend all likely landing spots, and the 8th Area Army and Vice Admiral Shigeyoshi Inoue’s 4th Fleet were ready to despatch reinforcements. The naval forces commanded by Ota were responsible mainly for Munda on New Georgia island and for Vila on Kolombangara island just to the north-west of New Georgia, while the army elements provided by the 38th Division and 51st Division were tasked with the defence of other areas under the overall command of Sasaki’s South-East Detachment.
Detailed planning of the US operation was entrusted to Turner’s 3rd Amphibious Force, which could call on the support of 533 aircraft, many of them embarked on the two fleet and three light carriers available, together with three battleships, nine cruisers, 29 destroyers and numerous other ships constituting Task Force 31.
In overall terms, TF31 comprised Turner’s own Task Group 31.1 (Western Landing Force) and Rear Admiral George H. Fort’s TG31.3 (Eastern Landing Force) 1.
Air support was the responsibility of Vice Admiral Aubrey W. Fitch’s Task Force 33 (Aircraft, South Pacific) comprising 258 fighters, 193 bombers and 82 heavy bombers shore-based on Guadalcanal, and the Air Search Unit with the PBY flying boats of the VPB-23, VPB-44 and VPB-77 squadrons based at Tulagi and Santa Cruz.
Standing by for deployment in the event of any major Japanese naval counter-offensive, but not in fact needed for combat operations, was Halsey’s Task Force 36 comprising Rear Admiral Walden L. Ainsworth’s Support Group A (TG36.1) with three light cruisers and five destroyers, Merrill’s Support Group B (TG36.2) with four light cruisers, four destroyers and four minesweepers, Rear Admiral DeWitt C. Ramsey’s Support Group C (TG36.3) 2.
The landings were planned in two phases for implementation on 30 June. At dawn, Fort’s Eastern Landing Force was to land the 4th Marine Raider Battalion (to be followed by the 1/103rd Infantry during the following day) at Segi Point on the south-eastern tip of New Georgia island, while elements of the 2/103rd Infantry landed at Oleana Bay on the southern side of Vangunu island, to the east of New Georgia island, before advancing to take Kaeruka and Vura on the western shore of Wickham Anchorage. After these initial objectives had been secured, the rest of Major General John H. Hester’s 43rd Division (plus additional units) of Turner’s Western Landing Force would land its 172nd Infantry on the northern shore of Rendova island, just to the south of Munda at the western end of New Georgia island. From Rendova island the 43rd Division would then cross to New Georgia island, land at Zanana some 5 miles (8 km) to the east of Munda, and close on the airfield with air support from a strip improvised at Segi Point.
The Japanese submarine Ro-103, which had sunk the 7,440-ton transports Aludra and Demios of a convoy returning from Guadalcanal near San Cristobal on 23 June, reported a US transport fleet on 29 June, but the local Japanese command wrongly assessed this as a supply convoy bound for Guadalcanal. During the night 29/30 June Merrill’s TG36.2 (Support Group B), comprising the light cruisers Cleveland, Columbia, Denver and Montpelier, and destroyers Waller, Saufley, Philip, Renshaw and Pringle, shelled the Japanese base on the Shortland islands group just to the south-east of Bougainville, while the minelayers Preble, Gamble and Breese laid a minefield without being detected.
Early on 30 June Turner’s TF31.1 landed the leading wave of Hester’s 43rd Division on the very northern tip of Rendova island. Air support was provided by the land-based warplanes of Fitch’s Aircraft, South Pacific command. The force which was landed on Rendova island, across a narrow strait from Munda and within artillery range of Munda airfield and likely future landing beaches, comprised the 172nd Regimental Combat Team and an artillery unit. Scouting forces were also landed on the barrier islands lying to the south-east of Munda. Although poor weather and heavy surf resulted in a confused landing, the Rendova assault was opposed by only 300 Japanese troops, whose commander was killed almost at once and who were quickly overcome, the survivors fleeing into the inland hills. The Japanese coastal batteries at Munda expected the landings to be made there, and did not open fire until after it had become clear the landings were in fact being made on Rendova island. The destroyer Gwin was damaged off Munda by the fire of a shore battery and had to withdraw, but the Japanese batteries were then silenced by destroyer gunfire.
The Japanese naval surface force at Rabaul was so inferior to the US naval forces that its single cruiser and eight destroyers made no effort to intervene, but there were a number of Japanese air raids against the US forces. A fighter sweep at 11.15 by 27 Mitsubishi A6M Reisen 'Zero' fighters sustained heavy losses from US fighters. A much larger raid at 15.50 by 25 Mitsubishi G4M 'Betty' medium bombers of the 702nd Kokutai and 705th Kokutai escorted by 24 A6M fighters was also intercepted by US fighters, but a few G4M bombers managed to break through and attack Turner’s retiring transports. McCawley, the 9,600-ton transport vessel which was also Turner’s flagship, was hit in the engine room and had to be abandoned, Turner shifting his flag to the destroyer Farenholt. Some 17 of the G4M bombers were shot down, however. A later attack by eight Aichi D3A 'Val' dive-bombers was unsuccessful, and three were shot down.
McCawley was so badly damaged that Turner was discussing whether to scuttle the ship when two torpedo hits settled the matter. These torpedoes had been fired by US PT-boats, which had been informed that there would be no US ships in Blanche Channel.
The main landings, made at several points in southern New Georgia in the area just to the east of Munda, were successful and met no effective resistance.
The basic plan for land operations had been altered at the last minute when coastwatchers reported that the Japanese were moving large numbers of troops toward the Segi Point area. Thus Currin’s 4th Marine Raider Battalion of the Eastern Landing Force was landed on 21 June and secured the Segi Point area against only limited opposition. The Seabees of the 47th Construction Battalion immediately began to develop an airstrip which would be operational within two weeks, while Currin undertook an attack to the north-west against Viru Harbour, whose capture on 1 July secured the US position at Segi Point.
The planned landing at Viru Harbour had been thwarted by a 2.95-in (75-mm) piece of coastal artillery which the Marine Raiders from Segi Point had been unable to put out of action. The men of the Viru Occupation Unit were therefore diverted to Segi Point, and Viru was taken on the following day by Marine Raiders with the help of heavy air support.
The Wickham Anchorage Occupation Unit, which landed in Oleana Bay, was misdirected in the dark and lost several landing craft, but came ashore without meeting opposition and then advanced overland to take the Japanese garrison at Kaeruka from the rear, thereby securing the anchorage on 3 July.
On 1 July the second wave of the US operation, with three tank landing ships, arrived off Rendova. The Japanese submarine Ro-101 was damaged by Radford.
On 2 July Vice Admiral Junichi Kusaka’s 11th Air Fleet undertook a raid with 24 army bombers and 24 army fighters supplemented by 20 A6M naval fighters. The US air cover was grounded by bad weather in the southern part of the Solomon islands group, and the attackers used the high ground in the centre of Rendova island to shield themselves from radar, achieving complete surprise: the US losses were 59 men killed and 77 wounded, and there was also considerable material damage, including the destruction of the newly established base hospital. That night, the light cruiser Yubari and nine destroyers entered the Blanche Channel and bombarded the new base on Rendova island, but their spotting was highly inaccurate and no significant damage was done. The Japanese force was engaged by PT-boats without effect.
Before the start of 'Toenails', there had been no final decision about the position at which the Munda assault force was to be landed, and reconnaissance patrols now reported that while Lahaina beach, some 2 miles (3.2 km) to the east of Munda, was heavily fortified, Zanana beach, about 5 miles (8 km) from Munda, was undefended. Advance units of the 43rd Division therefore began to land here on 2 July, and the main assault was planned for 5 July at Zanana. The logistical build-up had meanwhile been shifted to the barrier islands, which had firm coral terrain more suitable for supply dumps than the muddy terrain of Rendova.
During the night of 4/5 July the US destroyer transports Dent, Talbot, McKean, Wafers, Kilty, Crosby and Schley started the 'Broccoli' landing of three battalions (the 1st Marine Raider Battalion and the 3/145th Infantry and 3/148th Infantry totalling 2,600 men) of the Northern Landing Force’s 37th Division at Rice Harbour near Bairoko in the Kula Gulf, to the north of Munda, in preparation for a US pincer movement on Munda. The landing beaches had been cleared by people of the local population, who also started to cut two trails, in the direction of the Japanese stronghold at Enogai Inlet, to supplement the one existing trail. A substantial part of 3/148th Infantry had been landed too far to the north, and would be several days before this battalion joined the rest of the Northern Landing Force as it pushed to the south-west toward Enogai Inlet.
Cover for this landing had been provided by Ainsworth’s TG36.1 with the light cruisers Honolulu and St Louis, and destroyers Nicholas, Strong, O’Bannon, Chevalier and Taylor.
The Japanese had meanwhile decided to make a major reinforcement of their forces on the New Georgia group of islands, and the destroyers Mochitsuki, Mikatsuki and Hamakaze under the command of Captain Orita, carrying 1,200 men of the 13th Regiment and 229th Regiment, departed the Shortland islands group, to the south of Bougainville island, on 4 July. This force now encountered Ainsworth’s three light cruisers and nine destroyers. The destroyer Strong was struck by a torpedo launched at extreme range by the Japanese destroyers, which had been warned of the US presence when Ainsworth had ordered a bombardment of Vila. The resulting detonation of the destroyer’s depth charges damaged the nearby Chevalier as Strong started to sink. The Japanese destroyers then retired without landing their troops.
On 5 July Yubari was damaged by a mine off Buin.
On 2/3 July the 169th Infantry and 172nd Infantry of the 43rd Division crossed to New Georgia island and, after their landing at Zanana, their leading units began to advance to the west in the direction of the Bariki river and Munda. By 5 July both regiments were wholly ashore, and extra pressure on the Japanese then began to develop as the Northern Landing Force came ashore at Rice Anchorage with the twin objects of preventing the arrival of Japanese reinforcements from Kolombangara island (in which the Americans were unsuccessful) and of advancing to the south against Enogai Inlet and Bairoko Harbour, and so threaten Munda from the north.
Inspired by the relative success of the ‘Tokyo Express’ high-speed nocturnal runs of destroyer forces to deliver men, equipment and vital supplies to their forces on Guadalcanal late in 1942, the Japanese tried to repeat the tactic for the New Georgia campaign, and an initial consequence was the naval Battle of Kula Gulf, which was fought in the early hours of 6 July off the west coast of Kolombangara island, lying just to the west of New Georgia island.
On 5 July Ainsworth, TG36.1’s commander, was informed as a result of ‘Ultra’ intelligence decrypts that the Japanese were about to attempt a reinforcement operation from Buin at the south-eastern tip of Bougainville island. Pulling back after bombarding Vila on Kolombangara island and Bairoko on New Georgia, with a view to a replenishment rendezvous in the Coral Sea, TG36.1 comprised the light cruisers Helena, Honolulu and St Louis, and fleet destroyers Jenkins, Nicholas, O’Bannon and Radford. Ainsworth received his orders to make at high speed to the north-west past New Georgia and, after swiftly completing his ships' replenishments at Tulagi, raced to the north-west to effect the desired interception. Ainsworth had not been able to meet and discuss tactics with his ships' captains, but they had trained together and were therefore familiar with the core battle plan. This called for a radar-directed gunnery duel at medium range between 8,000 and 10,000 yards (7315 and 9145 m). Ainsworth assumed that his force would have a clear radar advantage and that the Japanese torpedoes would be ineffective at this range: events were to prove the falsity of both assumptions. By this time the Japanese had begun installing radar on their lighter warships, and Niizuki was equipped with the latest equipment; and the 'Long Lance' torpedo possessed a considerably greater range than Allied intelligence realised. Ainsworth also planned to adhere to the column formation, with destroyers in the van and rear, and the cruisers in the centre. The Americans had still not learned the lessons of the Battle of Tassafaronga.
At 01.16, in the Kula Gulf between Kolombangara and New Georgia, the US force of three light cruisers and four destroyers met the Japanese force of 10 destroyers, of which seven were carrying some 3,000 troops bound for Vila, which was being used as a staging point on the maritime route to Munda.
Commanded by Rear Admiral Teruo Akiyama, the Japanese destroyer force comprised the 1st Transport Group (Mochizuki, Mikazuki and Hamakaze), 2nd Transport Group (Amagiri, Hatsuyuki, Nagatsuki and Satsuki) and Support Group (Niizuki, Suzukaze and Tanikaze).
Cruising between the two transport groups, it was the destroyers of the Support Group which were the first to come under US attack. Ainsworth was overconfident in his radar advantage and unaware that his force had been detected, and closed the range. TG36.1’s cruisers opened fire at 01.57 and rapidly turned the van destroyer, Niizuki, into a blazing and sinking wreck; Akiyama was killed. The US destroyers held their fire until they could launch torpedoes, and this kept them out of the action until a late stage of the engagement. The van destroyers in fact failed to get a good torpedo solution, and the rear destroyers missed. Helena had expended all her flashless powder during the previous night’s operations, however, and was forced to use smokeless powder, thereby illuminating herself to the Japanese ships with every salvo. Two of the Japanese destroyers launched their 24-in (610-mm) ‘Long Lance’ torpedoes at about the time Niizuki was crippled, and Helena steamed straight into their path. The ship was fatally damaged, her bow being blown off and her keel broken, and quickly sank.
This initial exchange was followed by an indecisive gunnery duel. While the US and Japanese warships were exchanging gunfire, and at about 05.00 Amagiri and Nicholas traded torpedo and gunfire salvoes, in which the former sustained moderate damage, the Japanese nonetheless managed to land 850 out of the 2,600 reinforcements for New Georgia. With ammunition running low, Ainsworth ordered a withdrawal, and the Japanese did likewise.
During the Japanese withdrawal, Nagatsuki ran aground and could not be pulled free. Aircraft from Henderson Field on Guadalcanal attacked the ship on the following day, after her crew had abandoned ship, setting the destroyer on fire, and at about dusk her magazines exploded.
The Americans had erred in assuming they were undetected, in incautiously closing to within torpedo range, and in relying on gunfire rather than their own torpedoes. As a result, the superior US force was unable to achieve anything but a tactical draw.
Radford and Nicholas both remained to rescue Helena’s survivors and, during the process of recovering more than 750 men, had to re-engage the Japanese three times. Amagiri escaped and was the ship which later rammed and cut in half Lieutenant John F. Kennedy’s PT-109 in the Blackett Strait to the south-west of Kolombangara. The US Navy lost 186 men killed in the Battle of Kula Gulf, while the Japanese navy lost 324 men killed. Even so, the arrival of 850 of the reinforcements at Vila allowed Sasaki to move one of his battalions from Vila to Munda.
So far the US land operations had proceeded much as planned, though very much more slowly than anticipated because of acute supply difficulties, appalling terrain and weather, an increasing incidence of disease, and strengthening Japanese resistance. The Northern Landing Force drove off a Japanese patrol and the 1st Marine Raider Battalion seized the village of Triri on Enogai Inlet on 7 July and then, in expectation of a counterattack by the 6th Kure Special Naval Landing Force, dug in and awaited the supplies it so desperately needed. Meanwhile the 3/148th Infantry established a block on what it believed to be the main trail from Bairoko to Munda, and it was nine days before the Americans realised that the Japanese were un fact using a rail farther to the west and withdrew their roadblock. On 11 July Enogai was taken, and supplies could now come in by ship.
On the night of 6/7 July, however, the Japanese had launched a major counterattack against the inexperienced 169th and 172nd Infantry and came close to destroying the 169th Infantry before Hester’s personal intervention rallied the Americans. The 169th Infantry and 172nd Infantry then advanced once again, although the rate of their progress was too slow to please senior US commanders, especially after another Japanese counterattack on 16/17 July.
The US attack on Munda was becoming steadily slower. The terrain between Zanana and Munda is a chaotic jumble of streams, ravines and rocky hills covered with a dense tangle of jungle. Moreover, the 43rd Division was a National Guard unit with no previous combat experience, and entire columns were held up by individual snipers. The 3/169th Infantry performed particularly poorly, failing to secure its perimeter at night. By 9 July the two attacking regiments had run up against the main Japanese defences, and a major attack scheduled for that morning bogged down almost before it had begun in spite of heavy artillery and air support. The 169th Infantry made little progress against a belt of pillboxes across two ridges, between which the main trail from Zanana and Munda ran. While the 172nd Infantry advanced slightly on 10 July, it too was soon bogged down. The 169th Infantry now began to suffer a high incidence of combat fatigue, much of which may have been literal exhaustion.
The US supply situation was now acute, with nearly half the combat troops in the two attacking regiments diverted to bringing up supplies from Zanana. In order to shorten his supply lines, Hester decided on 11 July to send the 172nd Infantry to secure Laiana from the rear while the 169th Infantry continued its advance. It has been argued, with some justification, that this was an egregiously incorrect decision on the grounds that Hester should have used either his reserves on Rendova or the beach force at Zanana to carry out a landing with full air and naval gunfire support. Instead, Sasaki correctly calculated the US intent, and both regiments were fought to a halt.
The Americans attempted to break the deadlock on the night of 11/12 July by hitting the Japanese lines with a heavy bombardment from the warships of Merrill’s task force. In 40 minutes the ships fired 3,204 6-in (152-mm) and 5,470 5-in (127-mm) rounds: the bombardment accomplished little, for Merrill had been ordered to target an area no less than 1 mile (1.6 km) from the Japanese lines to provide a large margin of safety for nearby US troops, but this also served to protect the Japanese troops facing them. Moreover, as the bombardment was not followed by any land attack for several hours, its shock value was wasted. On the following day, the 172nd Infantry was still some 900 yards (825 m) from Laiana when it was cut off from the 16th Infantry by Japanese infiltrators.
Meanwhile the Japanese had once again attempted to run reinforcements and supplies to bolster their forces in New Georgia. Sasaki had received 3,000 reinforcements delivered in 16 barges, and then the delivery of another 1,200 men was organised for the night of 12/13 July, resulting in the naval Battle of Kolombangara. The Japanese ‘Tokyo Express’ reinforcement force, under the command of Rear Admiral Shunji Izaki, and comprising the light cruiser Jintsu and destroyers Mikazuki, Yukikaze, Hamakaze, Kiyonami and Yugure, together with the destroyer transports Satsuki, Minazuki, Yunagi and Matsukaze, made the run down ‘The Slot’ from the upper part of the Solomon islands group to land 1,200 troops at Vila on Kolombangara by way of the Kula Gulf.
An Allied force, commanded by Ainsworth and comprising the light cruisers Honolulu, St Louis and New Zealand Leander, and destroyers Nicholas, O’Bannon, Taylor, Jenkins, Radford, Ralph Talbot, Buchanan, Maury, Woodworth and Gwin, was deployed in a single column with five destroyers in the van followed by the cruisers and the other five destroyers in the rear.
The Western Landing Force had delivered men of the 37th Division to attack Munda the week before, and the Northern Landing Force had just delivered three battalions to Rice Anchorage to seize Bairoko. Ainsworth’s task was to protect the northern beach-head from attack by the ‘Tokyo Express’ and if possible to prevent further Japanese reinforcements from landing.
At 01.00 on 13 July the Allied ships established radar contact about 20 miles (32 km) to the east of the northern tip of Kolombangara. Once again, and just as erroneously, Ainsworth assumed he had complete surprise, but the Japanese had been aware of the Allied force for almost two hours. The US destroyers increased speed to engage the Japanese force, while the cruisers turned to deploy their main batteries. The Japanese destroyers had already launched torpedoes, however, and now turned away. Jintsu engaged the Allied ships, all of whose fire was concentrated on the largest Japanese ship, and Jintsu was reduced to a wreck while Leander was struck by a torpedo and, severely damaged, retired from the battle escorted by Radford and Jenkins. Jintsu was finally broken in two by torpedo hits and sank at about 01.45 with the loss of almost her whole crew including Izaki.
Ainsworth pursued the Japanese destroyers, but both St Louis and Honolulu took torpedo hits and were damaged, while Gwin was struck amidships and so severely damaged that she had to be scuttled at 09.30 on the following morning. Honolulu and St Louis were out of action for several months, while Leander was under repair for a year.
Except for Jintsu, the Japanese force escaped undamaged and the transport destroyers successfully landed 1,200 men at Vila. The Japanese had won a tactical victory, even though they had lost 482 men to the Americans’ total of 89, but despite the severe cost Ainsworth had accomplished his mission of preventing an attack on the US Marine beach-head, and combined with the earlier Battle of Kula Gulf, the Battle of Kolombangara successfully deterred the Japanese from future use of Kula Gulf in reinforcing Munda. After the Battle of Kolombangara, the Japanese chose to use Vella Gulf, Blackett Strait, and the more constricted passage between Wana Wana and Arundel islands, resulting in a series of nightly attacks by US destroyers and PT-boats against their reinforcement efforts.
On the next day, the 172nd Infantry at last cleared Liaina, and this made it possible for reinforcements and supplies to be delivered, the former including combat engineers and one company of US Marine tanks. But by then a full battalion of Sasaki’s troops had entrenched itself between the 172nd Infantry and the 169th Infantry. Although on 13 July the 3/169th Infantry finally took Reincke Ridge, the heavily fortified ridge to the south of the main trail, the battalion was only just able to hold this important position against ferocious Japanese counterattacks: in the 24 hours after its seizure of the ridge, the battalion suffered 101 casualties. The whole regiment was on the verge of collapse, with only a trickle of supplies reaching it a contested trail and by parachute drop.
At this point, Hester’s immediate superior, Major General Oscar W. Griswold, commander of the XIV Corps, arrived for a personal evaluation of the current situation. Discovering that there were large number of casualties as a result of combat fatigue and also of 'friendly fire' incidents, and immediately appreciating that the US offensive was clearly stuck in its tracks, Griswold urged Halsey to send immediate reinforcements. Halsey responded by ordering major elements of two more US formations, Major General J. Lawton Collins’s 25th Division and Beightler’s 37th Division, to New Georgia. Halsey also sent his senior army commander, Lieutenant General Millard F. Harmon, the Army Forces, South Pacific commander, to New Georgia with instructions to do whatever was needed to take Munda. Harmon immediately concluded that new leadership was needed. Hester had already relieved the commander of the 169th Infantry and one of its battalion commanders, but now Hester himself was removed from command when, on 15 July, Harmon ordered Griswold to relieve Hester as commander of the New Georgia Occupation Force and establish the headquarters of the XIV Corps headquarters at Rendova. On 24 July, Turner was rotated out of the theatre and was succeeded as the South Pacific Amphibian Forces commander by Rear Admiral Theodore S. Wilkinson.
The change in the command structure overcame a problem which should never have been permitted to develop. Hester had been expected simultaneously to command the New Georgia Occupation Force and the 43rd Division with a single headquarters staff. With Griswold now present as corps commander, Hester could focus on fighting his division. However, Hester soon lost his divisional command as well, being replaced by Major General John R. Hodge on 29 July after Harmon had come to the conclusion that Hester was completely exhausted.
On the same day, there was a fierce air battle over Rendova. The effects of attrition on the quality of the Japanese air forces was evident as 40 Japanese aircraft were shot down but only three US warplanes were lost.
Like the Americans, the Japanese had sent reinforcements to New Georgia. The 13th Regiment had been brought in by barges from Kolombangara, evaded the marines' roadblock at Enogai Inlet, and had started to assemble deep in the jungle in the area to the north of the US forces' poorly guarded right flank. Although US patrols had identified the presence of troops of the 13th Regiment to the north of the battle zone, the significance of this development was at first not fully appreciated.
On 16 July, the 1/169th Infantry took Kelley Hill, just to the west of Reincke Ridge, but by the next morning the battalion was nearly surrounded by the 3/229th Regiment. Sensing the possibility of victory on the ground, Sasaki had launched a major counterattack. The 229th Regiment attacked the US front line to pin the Americans while the newly arrived 13th Regiment moved round the US flank, cutting the trail to Zanana and raiding the 43rd Division’s rear areas. In response, Griswold deployed the newly arrived 148th Infantry of Beightler’s 37th Division to Zanana, and by 20 July contact had been re-established with the 169th Regiment.
The blocking force at Enogai Inlet had also stalled in its efforts to cut the communications between Munda and Vila. An attack on 20 July failed to receive the air support it needed, and thus was driven back. On 21 July, however, after receiving considerable air support from 250 aircraft from Guadalcanal, the Marine Raiders finally enveloped the Japanese at Bairoko and cut their supply line. The Marine Raiders were reinforced and resupplied on 24 July by a convoy escorted by Captain Arleigh Burke. This gave the Marine Raiders sufficient strength to hold their roadblocks, but not to advance on Munda.
Griswold launched a fresh offensive on 25 July after road construction had improved his units' supply situation. The 43rd Division and 37th Division were now ashore and led the assault, while the exhausted 169th Infantry was withdrawn into corps reserve. The new offensive started at dawn after Burke’s destroyers had laid down a heavy bombardment on the area in front of the 43rd Division: some 4,000 5-in (127-mm) rounds were fired at a density of 70 shells per 1,000 sq yards (50 shells per 835 m²). Despite its concentration, the bombardment was not sufficient to destroy the Japanese troops, some of whom escaped the deluge of shells by moving as close as possible to the Americans. After the battle, an investigation led by Wilkinson concluded that 200 shells per 1,000 sq yards (167 shells per 835 m²) was needed to effect the complete neutralisation of Japanese troops in field works. Only a direct hit was capable of destroying the strongest of the Japanese bunkers.
A lavish scale of air support was also provided in the days before the offensive, with attacks on almost every day by two or three squadrons of Douglas SBD Dauntless dive-bombers and Grumman TBF Avenger level bombers using 2,000-, 1,000- and 500-lb (907-, 454- and 227-kg) bombs. However, the limitations of close air support at this time meant that the majority of the bombs were dropped well behind the Japanese line to avoid the possibility of 'friendly fire' casualties.
The offensive therefore made only slow progress in spite of support from flamethrowers and US Marine Corps tanks, which found they could not traverse the terrain. However, by 31 July, the Americans had overrun Shimizu Hill and thereby unhinged the Japanese line. The Allies counted no less than 46 log and coral pillboxes and 32 other positions on Bartley Ridge, which the Japanese finally abandoned on 28 July. Meanwhile the 148th Regiment had ranged far to the north and west, but was forced to pull back under pressure from the 13th Regiment.
On 1 August the US perceived the first evidence that the Japanese were withdrawing. Griswold ordered that patrols be sent forward and, after these had reported few signs of the Japanese, committed his forces to a general advance. There was little resistance, and by the end of the day the 103rd Infantry had advanced to the edge of Munda airstrip. The Japanese had in fact suffered far heavier losses to the unremitting US bombardment than Griswold and his senior subordinates had realised. Some Japanese infantry companies had been reduced to a mere 20 men, and the 229th Regiment had been whittled down to just 1,245 men, with an especially low proportion of officers to other ranks. Unknown to the Americans, Sasaki had ordered a retreat three days earlier, instructing those men who could not retreat to fight to the death.
The remaining Japanese centre of resistance in the Munda area was Bibilo Hill to the north of the airstrip, and this did not fall until 5 August after its defenders had been shattered by the fire of mortars and 37-mm guns. After nearby Kokengolo Hill had been afforded the same treatment, organised Japanese resistance in the Munda area ended.
The last significant naval engagement off New Georgia was the Battle of the Vella Gulf on the night of 6/7 August to the west of Kolombangara’s west coast. The Japanese destroyers Arashi, Hagikaze, Kawakaze and Shigure, the first three carrying troops and supplies, were steaming by their usual route toward Kolombangara. The convoy, spotted at 16.30 near Buka, was expecting at night action, which it would get from TG31.2, which comprised the destroyers Craven, Dunlap, Lang, Maury, Stack and Sterett.
The US Navy had no cruisers available, and for the first time this would be a destroyer-versus-destroyer action in which the US destroyers would not have to act as screens for cruisers and would have a numerical advantage of six to four.
Under the command of Captain Kaju Sugiura, the Japanese column entered the Bougainville Strait at 21.00 and by 23.20 was to the north-east of Vella Lavella, where its course was changed to south-south-east. Sailing orders had ordained that the four ships follow one another at 545-yard (500-m) intervals, but Shigure, her engines overworked, was now lagging by 1,500 yards (1370 m). She was especially concerned because of an aeroplane spotting of possible US ships in the area, and had trained her torpedo tubes to port, since the shore of Vella Lavella on her starboard side was clear of ships. Visibility against the black background of Kolombangara was only 2,000 yards (1830 m), and at 23.44 Shigure’s look-outs sighted several ships.
Under the command of Captain Frederick Moosbrugger, TG31.2 was steaming into two parallel columns with Dunlap, Craven and Maury to port, and Lang, Sterett and Stack to starboard, both columns heading to the north-north-east. Dunlap’s radar detected ships at 23.33 in a position some 12 miles (19 km) to the north. The advantage was with the US ships, for by continuing on their current course, they would close the distance for a port torpedo attack at a range of 6,000 yards (5485 m). At 23.41 Craven, Dunlap and Maury launched 24 torpedoes, three minutes before Shigure made her sighting. Just as Shigure launched a salvo of eight torpedoes, three torpedoes struck Arashi in her engine room and the Japanese ship burst into flames, then a few minutes later she was hit by gunfire and another torpedo. Kawakaze took one hit from the same salvoes, causing her magazine to explode and setting her entire forward section on fire. Hagikaze also caught fire after being hit twice, and lost power. Kawakaze sank at 23.52, Arashi at 00.17, and Hagikaze at 00.18. Torpedoes barely missed Shigure, which had had time to turn and comb their tracks. But Shigure’s torpedoes also missed their targets. She reversed course, made smoke, and retired to the north at 23.45, after passing through the wreckage of Arashi and Hagikaze.
The port column of TG31.2 turned to the east in order to avoid the Japanese torpedoes at 23.44, and then almost to the south at 23.52 to rake the ships still afloat. The starboard column turned to the west at 23.52, also opening fire on the Japanese ships. The two columns then re-formed and retired to the south. Only sporadic gunfire had come from the crippled destroyers, and the US ships suffered no damage.
The Japanese lost 1,210 soldiers and sailors, and only 310 men were rescued from Kolombangara. The loss of three destroyers and more than 1,000 men was a severe setback for the Japanese, and it was a humiliation to Japanese destroyer men who had intense pride in their performance record, particularly in night torpedo battles. It also showed that US destroyers, when they were not tied to the task of screening larger ships, could also win night battles.
By 15 August the airfield at Munda was in full US service as Hodge’s 43rd Division moved to the north to assist the 37th Division against the 6th Kure Special Naval Landing Force at Bairoku Harbour, the last Japanese outpost on New Georgia island, which fell on 22 August after the surviving defenders had been evacuated by barge to Kolombangara island.
The task of mopping up Japanese survivors in the rest of the New Georgia group continued until 25 August. On 19 August the Japanese were cleared from Baanga island, from which they had been dropping harassing fire on Munda, by units of the 43rd Division. On 24 August the small harbour at Bairoki was finally taken and Zieta, at the south-western extremity of the island, was cleared.
Yet the campaign on New Georgia island had dealt with only half of the Japanese garrison in the New Georgia islands group. During the course of the New Georgia fighting, the other garrisons had been reinforced to some 10,000 men despite losses during the naval battles of the Kula Gulf on 5/6 July and Kolombangara on 12/13 July, which had been Japanese tactical victories. Most of this Japanese strength was disposed for the protection of the airfield at Vila on Kolombangara island, but there were also Japanese forces on Arundel and Vella Lavella islands, and these three bastions had to be eliminated before the US position in the island group could be considered secure. As noted above, Turner had moved to a position in the Central Pacific Area and been succeeded by Wilkinson. This equally capable commander had already planned to attack Kolombangara as soon as the New Georgia operation was virtually complete, but then a more attractive alternative was perceived, namely the bypassing of the island by landings on Arundel and Vella Lavella, which would isolate the Japanese defenders on Kolombangara and condemn them to ‘wither on the vine’ as the US forces pushed up the chain of the Solomon islands group with the aid of air support from Munda and an airstrip built on Vella Lavella.
Thus was born the concept of bypassing and isolating rather than engaging and destroying Japanese bastions wherever possible, with a consequent saving in US lives and an acceleration of the rate of advance. It had been the protracted nature of the fighting for New Georgia which convinced the Americans to rethink their strategy for the rest of the Solomon islands campaign. Halsey’s next attack therefore bypassed Kolombangara to land at weakly defended Vella Lavella in 'Dogeared', and the pattern of leapfrogging Japanese major centres of resistance came to characterise Allied operations for the remainder of the Pacific War.
Arundel island lies on the southern side of the Kula Gulf, and here Sasaki played his delaying role to the hilt. When the 172nd Infantry landed on 27 August, he allowed the US troops to come ashore unopposed and establish a beach-head. Then just as the Americans were feeling that the occupation of the island would be both easy and straightforward, Sasaki counterattacked in several areas, pinning the Americans and persuading them to call for reinforcement. The Japanese carried out an especially determined attack on 15 September, bringing the whole Allied effort on Arundel island to a halt, and with far fewer troops than his opponents. Griswold now ordered a larger-scale effort, including Marine Corps tanks, to drive the Japanese off the island. After vicious fighting on 17 and 18 September, the Japanese abandoned Arundel during the night of 20/21 September. This allowed Vila airfield to be neutralised by US artillery located on Arundel island’s northern shore.
As noted below, Halsey and other senior US commanders had by this time come to appreciate the tactical and operational sense of bypassing heavily fortified islands wherever and whenever possible. Thus all thought of taking Kolombangara island was forgotten and replaced by the idea of taking Vella Lavella island as this latter lies closer to Bougainville and Rabaul, was less well defended than Kolombangara island and, in Allied hands, would effectively neutralise Kolombangara island. Thus, a month before New Georgia was secured, a reconnaissance party was landed on Vella Lavella to gain information about Japanese strength and dispositions as well as to search out sites suitable for a landing operation. These men and their native guides managed to explore the island for a full week, completely avoiding contact with the Japanese, before on 31 July returning to Guadalcanal with thorough intelligence about the target. The village of Barakoma near the island’s south-eastern tip was then selected for the landing.
The 'Dogeared' invasion force comprised seven destroyer transports, three tank landing ships, two submarine chasers and 12 destroyers under the personal command of Wilkinson aboard one of the destroyers. Embarked were about 6,500 ground troops under the command of Brigadier General Robert B. McClure, the assistant commander of the 25th Division. Japanese warplanes attacked many Allied bases on the night of 14/15 August, but did not locate the naval force heading to Vella Lavella. On the ext morning, the disembarkation of two battalions of the 25th Division’s 35th Infantry began on the south-eastern tip of the island at Barakoma, and the Americans quickly secured a lodgement large enough to allow the construction of an airstrip with a 4,000-ft (1220-m) runway, and this came into service on 24 September.
The Japanese high command in Tokyo had already come to the decision, on 13 August, that no more troops were to be expended fruitlessly in the central part of the Solomon islands group. So rather than be reinforced and defended, Vella Lavella was to be used merely as a way station for the evacuation of the troops on Kolombangara, which had been bypassed by the Allies with the 'Dogeared' landing on Vella Lavella, to boost the Japanese strength on Bougainville which, the Japanese rightly estimated, was likely to be the Allies' next major target in the Solomon island campaign.
Horaniu on the north-east coast was selected as the necessary barge staging point, and on the night of 17/18 August two army companies and a navy infantry platoon were landed there in a little fleet of 20 barges and auxiliary vessels. Rear Admiral Matsuji Ijuin’s covering force of four destroyers (Sazanami, Hamakaze, Isokaze and Shigure) was met in 'The Slot' by Captain Thomas J. Ryan’s US force, also comprising four destroyers (Nicholas, O’Bannon, Taylor and Chevalier), which had been despatched to disrupt the Japanese operation. In the ensuing Battle off Horaniu, neither side lost any ships, though the Japanese suffered damage to two destroyers and lost four auxiliary vessels, but were nonetheless able to establish their barge staging base, which allowed the eventual evacuation of 9,400 men from Kolombangara island largely by barge despite of heavy losses to Allied aircraft. On 28/29 September a force of four Japanese destroyer transports, escorted by nine destroyers, evacuated 2,115 men from Kolombangara. A repetition of this effort on the following night resulted in an inconclusive long-range engagement between Japanese and Allied destroyer forces. Similar inconclusive engagements took place on the next three nights. By 4 October the Japanese had completed their evacuation, recovering 5,400 men, including Sasaki, by barge and another 4,000 by destroyer. In the process, they lost about one-third of their barges and 1,000 men.
The Allies decided to compress the remaining Japanese troops on Vella Lavella into a pocket in the north-western corner of the island and destroy out. The task was allocated to New Zealand forces, in the form of Brigadier L. Potter’s 14th Brigade Group of Major General H. E. Barrowclough’s 3rd Division, which had relieved the Americans on Vella Lavella. The New Zealanders began their pincer movement on 21 September, but the Japanese resisted so fiercely that it took until 5/6 October to drive them into a small lodgement.
On the night of 6/7 October, Ijuin commanded an operation in which the destroyer transports Fumizuki, Matsukaze and Yunagi, four submarine-chasers, four motor torpedo boats and four 'Daihatsu' class landing craft were to undertake the evacuation of the 600 Japanese troops remaining on Vella Lavella. Ijuin personally commanded a group of six destroyers (Akigumo, Isokaze, Kazagumo, Yugumo, Shigure and Samidare) sent to cover the operation against any US naval interference. Wilkinson hurriedly rerouted six destroyers, in two three-ship groups of destroyers, to attempt the interception of the evacuation. Only the first group (Selfridge, Chevalier and O’Bannon ), under the command of Captain Frank R. Walker, arrived in time to engage in combat, Walker opting not to wait for the arrival of Ralph Talbot, Taylor and La Vallette.
The resulting Battle of Vella Lavella began at about 23.00 as each side opened fire and launched torpedoes at a range of about 7,0000 yards (6400 m). The leading Japanese destroyer, Yugumo, was hit several times, lost her steering and, finished by a torpedo, sank at about 23.10. One of her torpedoes hit Chevalier, however, detonating the US destroyer’s forward magazine. O 'Bannon then collided with the crippled Chevalier, and for a time the two ships were locked together: Chevalier was so badly damaged that she had later to be sent to the bottom at about 03.00 by a torpedo from La Vallette. Selfridge attacked alone, and at 23.06 was hit by a torpedo and disabled. All three ships were severely damaged, and reinforcements were still 15 minutes away. However, the rest of the Japanese force turned away, having perhaps misidentified the three approaching destroyers as cruisers. The US personnel losses were 64 men killed, 47 men wounded and 36 men missing, while those of the Japanese were 138 men killed. Nevertheless, Ijuin had succeeded in keeping the US warships from interfering with the evacuation of 589 troops in the smaller vessels and craft.
The New Zealand attack therefore met no resistance whatsoever as the Japanese had already departed.
The US casualties in the New Georgia campaign had been 1,195 men killed and almost 4,000 wounded out of a committed strength of 32,000 men. The Japanese had lost about 2,500 dead out of their strength of 10,500 men. In the air fighting over the New Georgia campaign, the Americans lost 983 aircraft, and the Japanese 358 aircraft.
The 24th and 73rd Naval Construction Battalions then went to work on Munda airfield, which was thus able to accommodate the VMF-123 and VMF-124 fighter squadrons by 14 August. The main airstrip was soon extended to 6,000 ft (1830 m) and then to 8,000 ft (2440 m) by December 1943. The airfield soon became the most important in the Solomon islands group. A 4,500-ft (1370-m) runway was also built on Ondonga island some 6 miles (10 km) to the north-north-west of Munda. All were closed in March 1945.
Fort’s TG31.3 comprised the Viru Occupation Unit built round B Company, 103rd Infantry carried in the 1st Echelon comprising the high-speed minesweeper Hopkins, and the 2nd, 3rd and 4th Echelons each comprising one coastal transport and two or three tank landing craft; Task Unit 31.3.2 (Segi Point Occupation Unit) based on two companies each of the 4th Marine Raider Battalion and 103rd Infantry as well as the 20th Naval Construction Battalion carried in four echelons each comprising one coastal transport, two to four tank landing craft and five infantry landing craft; the Wickham Anchorage Occupation Unit comprising the 2/103rd Infantry and two companies of the 4th Marine Raider Battalion carried in the 1st Echelon comprising the high-speed minesweeper Trever and seven infantry landing craft, and the 2nd, 3rd and 4th Echelons each comprising one coastal transport, and between one and four tank landing craft; and the 12 PT-boats of the Russell Islands Motor Torpedo Boat Squadron.