The end of the fighting on New Georgia

On the night of 20–21 September 1943 the last Japanese soldiers defending the island of Arundel in the central Solomon Islands boarded barges and, covered by artillery fire, crossed the narrow Blackett Strait to neighbouring Kolombangara. That same night the Japanese also took off the small garrison of Gizo, an island further to the west. On the morning of 21 September the Americans, who had been fighting a hard battle in the jungle and mangroves of Arundel for nearly four weeks, occupied the abandoned positions. In the New Georgia group – leaving aside Kolombangara and the north-western tip of Vella Lavella – there was no longer any organised resistance.

War chronologies record under this date that the battle for the Solomons can be regarded as unofficially over. So sweeping a statement needs qualifying: what ended – and not quite completely – was the fighting in the central Solomons, which had begun in June with the landing on New Georgia. The Japanese had yet to evacuate Kolombangara and Vella Lavella, and the largest island of the archipelago, Bougainville, was still in their hands. The fighting there was to begin within a few weeks and to last, with interruptions, until the end of the war.

After Munda

The New Georgia campaign, planned by Admiral William Halsey as a swift one-division operation, dragged on into August and absorbed the strength of four. The Americans took Munda airfield, its main objective, on 5 August, and by the end of the month organised Japanese resistance on New Georgia itself had ceased. The retreating troops of Major General Noboru Sasaki crossed to Kolombangara, where, by American estimates, 10,000–12,000 Japanese soldiers and sailors had gathered. Halsey did not want to pay the same price a second time. On 15 August his forces bypassed Kolombangara and landed on lightly defended Vella Lavella, further to the north-west, to build an airfield of their own there and cut the Japanese garrison off from its supplies.

Arundel, a small, jungle-covered island between New Georgia and Kolombangara, lay where these plans intersected. Whoever held it controlled the Blackett Strait and the Diamond Narrows passage. For the Japanese it was a forward outpost of Kolombangara from which they could shell the Munda area; for the Americans it was a place from which their heavy artillery could hit the Japanese positions and Vila airfield on Kolombangara. After losing three destroyers in the Battle of Vella Gulf on the night of 6–7 August, the Japanese abandoned the idea of a counter-offensive on New Georgia and decided merely to delay the enemy’s further advance. In the second half of August they moved troops withdrawn from the islet of Baanga to Arundel.

Four weeks on Arundel

The American command expected no more than a minor action on Arundel. By American estimates the island was initially defended by some 200 men of the Japanese 229th Infantry Regiment, so a single regiment was sent there – the 172nd Infantry Regiment of the 43rd Division, part of General Oscar Griswold’s XIV Corps. On 27 August the regiment crossed from New Georgia through the Diamond Narrows and landed unopposed on the south-eastern tip of the island. It then split into two columns, which moved north along the east and west coasts through dense jungle and mangrove swamps. Progress was slow, and the men, who had been in action for weeks, were exhausted and racked by malaria. The first clash came only on 1 September on the east coast, near Stima Lagoon.

The Japanese refused to be drawn into open battle. They fired from long range, harassed American outposts at night, laid mines and booby traps, and their artillery on Kolombangara shelled the crossings. Resistance proved much stronger than expected. From 8 September Sasaki reinforced the garrison with battalions of Colonel Satoshi Tomonari’s 13th Infantry Regiment, which was not only to defend the island but also to obtain food and to delay the Americans long enough for other units to be withdrawn from Kolombangara. The Americans responded in kind: the 169th Infantry Regiment of the 43rd Division, two battalions of the 27th Infantry Regiment of the 25th Division, 4.2-inch chemical mortars and 155 mm guns arrived on Arundel in turn. At the peak, eight American infantry battalions were fighting there.

From 11 September the fighting in the north of the island was directed by the commander of the 27th Regiment, Colonel Douglas Sugg. His units cleared the Bomboe Peninsula and the islet of Sagekarasa, pushing the Japanese east, where the 172nd Regiment barred their way. On the night of 14–15 September Japanese reinforcements coming by barge from Kolombangara came under American artillery fire; Colonel Tomonari and two battalion commanders were killed. Even so, the Japanese launched a fierce counter-attack that halted the American advance.

The breakthrough came with tanks. Light tanks from the tank platoons of three Marine defence battalions – the 9th, 10th and 11th – were brought over from Munda to Arundel. On 17 September five of them, supported by infantry, destroyed a Japanese strongpoint and allowed the line to be moved forward several hundred metres; the next day the Japanese knocked out with anti-tank guns two tanks that had become separated from the infantry. On 19 September eleven tanks led the 27th Regiment’s attack on the last Japanese foothold on the Stima Peninsula. Japanese soldiers threw themselves at the tanks with magnetic mines, but the infantrymen covering the tanks shot them down at close range.

Meanwhile the American navy was cutting the night-time supply lines across the strait ever more effectively. The Japanese command concluded that there was no point in holding Arundel any longer, and on the night of 20–21 September the garrison withdrew to Kolombangara. Japanese artillery smothered the American positions with fire, while American guns and mortars shelled the departing barges. Some of the Japanese tried to swim across the strait; the sea later washed their bodies ashore. Minor mopping-up operations on the island continued after 21 September.

According to American accounts, the fighting on Arundel cost the Americans 44 killed and 256 wounded, and the Japanese some 345 killed and 500 wounded. The commander of the 43rd Division reportedly called it the most bitter fighting of the entire New Georgia campaign.

September in the central Solomons

As the fighting on Arundel was ending, New Zealanders were already relieving the Americans on Vella Lavella. On 18 September the 14th Brigade of the 3rd New Zealand Division landed there, and its commander, Major General Harold Barrowclough, took command on the island. A slow push began to drive several hundred Japanese soldiers towards the north-western tip of the island. On the south coast, at Barakoma, the Seabees were completing an airstrip, on which the first aircraft landed on 24 September. From the airfields at Munda and on Vella Lavella, Allied fighters would soon be covering the leap to Bougainville.

In the last weeks of August and in September American destroyers and PT boats hunted Japanese barges in the straits every night. After the Battle of Kula Gulf and the Battle of Kolombangara in July and the defeat in Vella Gulf, the Japanese navy supplied its cut-off garrisons mainly by barge, at night and with mounting losses. On Kolombangara food and medicine ran short, and more and more soldiers fell sick.

At the same time the second part of the plan, in which Halsey was working together with General Douglas MacArthur, was going ahead. At the beginning of September the Australians landed near Lae in New Guinea, and American paratroopers seized nearby Nadzab. The two offensives, conducted under Operation Cartwheel, were closing a pincer around Rabaul, the largest Japanese base in the South Pacific. At the Quebec Conference in August the Allies had accepted that Rabaul need not be captured: it was enough to surround it with air bases and cut it off. The experience of New Georgia – long, costly battles for every island – argued for bypassing strongly defended points, as had been done with Kolombangara.

What came next

Japan drew a similar conclusion from these months. At the end of September 1943 the Japanese high command adopted a new defensive concept, laying down the so-called Absolute National Defence Zone – a ring running from the Kurils through the Marianas and the Carolines to western New Guinea and Burma. Rabaul and the Solomons fell outside it; their garrisons were to delay the enemy for as long as possible rather than recover lost ground. It was in keeping with this logic that Arundel and Gizo were abandoned, and at the turn of September and October the Japanese navy took off the Kolombangara garrison by destroyer and barge over the course of a few nights. The last 600 or so soldiers on Vella Lavella were evacuated on the night of 6–7 October; their covering destroyers clashed with American ones in the Battle of Vella Lavella. According to the American official history, the Japanese thus saved some 9,400 men from the New Georgia group, and with that the fighting on Vella Lavella and the whole central Solomons campaign came to an end.

The next stage began swiftly. At the end of October New Zealanders landed on the Treasury Islands, and American Marine paratroopers carried out the raid on Choiseul to divert Japanese attention. On 1 November 1943 the 3rd Marine Division landed in Empress Augusta Bay on Bougainville. Among the troops on that island were soldiers evacuated from Kolombangara. The fighting for it dragged on – after the Australians took over the front in 1944 – until Japan’s surrender in August 1945. The Solomon Islands campaign, begun on Guadalcanal in August 1942, thus did not end in September 1943, either unofficially or officially. September 1943 did, however, close its hardest, central stage: the road to Bougainville and towards Rabaul opened for the Allies, and the Japanese went over to a defence in which all they could hope for was to gain time.