The fighting for Hill 700

At 5.45 a.m. on 8 March 1944 Japanese artillery hidden on the mountain ridges above Cape Torokina opened fire on the American beachhead on Bougainville. The shells fell above all on the Piva airfields, from which the Americans had been attacking Rabaul for four months. So began the only major counter-offensive that the Japanese 17th Army managed to mount against the beachhead seized in November 1943 – the Americans called it the second battle of Torokina. Its fiercest focus in the first days was Hill 700, a steep ridge in the centre of the American defence line, which the Japanese infantry assaulted from the night of 8–9 March. On 13 March the remnants of the attackers began to withdraw from it, but the battle for the beachhead went on for almost two more weeks, until 25 March.

What happened on 8 and 13 March

War chronologies record that on 8 March the Americans were attacked by the Japanese on Hill 700 and that the fighting “would last five days”, and that on 13 March the Japanese ended their unsuccessful assault there. This is broadly true, but two points need clarifying. The Japanese counter-offensive did indeed begin on 8 March, but only with an artillery bombardment and patrol skirmishes; according to the American official history, the Japanese 23rd Infantry Regiment, which was to have taken the hill that day, failed for unexplained reasons to advance. The assault began some tens of minutes after midnight on 9 March. The five days therefore span the period from the first bombardment to the moment when the Americans restored their original line on 12 March and the Japanese began their retreat on 13 March. The second qualification is that the withdrawal from Hill 700 was not the end of the Japanese offensive. The fighting for Hill 260 and along Taylor’s Creek and Cox’s Creek continued, and the last attack, on the night of 23–24 March, was the biggest of all.

A beachhead the Japanese did not want to attack sooner

The US 3rd Marine Division had landed in Empress Augusta Bay on 1 November 1943, and on the night of 1–2 November Rear Admiral Merrill’s cruisers and destroyers had repulsed a Japanese naval counter-attack in the Battle of Empress Augusta Bay. The commander of the 17th Army, General Harukichi Hyakutake – the same man who had lost the Guadalcanal campaign – at first, according to American historians, took the landing at Torokina for a diversion ahead of a landing in the south of the island, where his main forces were stationed. Only at the end of December did he and his staff conclude that the Americans had no intention of moving out of the beachhead or of landing elsewhere, but were building airfields on it. It was then that planning for a counter-offensive began.

The Japanese calculations rested on false data. The 17th Army staff believed that there were some 30,000 Americans in the beachhead, of whom only 20,000 were front-line troops. In reality General Oscar Griswold’s Army XIV Corps, which had taken over the beachhead from the Marines in December, numbered about 62,000 men including naval units. The defence line, some 21 kilometres long, was held by two experienced divisions: on the left, north-western wing and in the centre General Robert Beightler’s 37th Infantry Division, and on the right, eastern wing the Americal Division of General John R. Hodge. The Allied forces in the South Pacific, to which the beachhead belonged, were commanded by Admiral William Halsey.

The Japanese plan

On 21 January 1944 Hyakutake’s superior, the commander of the Eighth Area Army, General Hitoshi Imamura, flew in to Bougainville from Rabaul and ordered the offensive to begin at the start of March. According to the Japanese historian Hiroyuki Shindō, the date was dictated solely by food stocks. After the American raids on Rabaul, the destruction of the base at Truk and the New Zealanders’ occupation of the Green Islands in mid-February, supplies from Rabaul had practically ceased, and the attack had to be made before the soldiers began to starve. Rations for a mere two weeks had been accumulated.

Throughout January and February engineers built roads and bridges in the interior of the island, while the units chosen for the attack trained in jungle fighting. By barge and on the backs of porters, an artillery concentration was hauled across the mountains that American historians regard as the largest the Japanese had yet assembled in the Pacific: according to a post-war American study, 168 guns, including four 150 mm howitzers. The assault forces came mainly from General Masatane Kanda’s 6th Division, a veteran unit of the war in China, and from two battalions of the 17th Division. They were divided into three groups named after their commanders. General Shun Iwasa’s group, built around the 23rd Infantry Regiment, was to take Hill 700 in the centre of the American line on 8 March and then advance on the Piva airfields. Colonel Toyoharei Muda’s group was to attack Hills 260 and 309 from the east on 10 March, and Colonel Isaoshi Magata’s group from 11 March – from the north, across low-lying ground, against the 129th Infantry Regiment. By 17 March all three were to meet at Cape Torokina. The US Army official historian John Miller states that 15,400 or 19,000 soldiers were earmarked for the offensive; Shindō, that some 9,500 went directly into action.

The orders of the day were grandiloquent. Hyakutake called on his soldiers to “wipe out the shame of their brothers from Guadalcanal” and to deepen the red of their banners “with the blood of the American scoundrels”, while Kanda declared that there would be no rest until the enemy had been humbled. Miller, who quoted both orders in the official history, commented on them with a dry footnote referring to the verse in the biblical Book of Proverbs (16:18) about the pride that goes before a fall.

The Americans wait

The Americans knew of the preparations almost from the start. Information came from radio interception, patrols deep in the island, aircraft and the interrogation of prisoners. At the forward outpost of Ibu, on the Numa Numa trail, stood troops of the 1st Battalion from Fiji; in February, when larger Japanese forces surrounded it, the battalion withdrew into the beachhead, taking some two hundred local civilians with it. Documents found on dead Japanese made it possible to reconstruct the plan of attack and the composition of the attacking units, and extracts from them were even pinned up on company notice boards.

Griswold, who had learnt on New Georgia how costly it was to attack the Japanese in the jungle, decided to wait for them in fortified positions. Bunkers, wire entanglements and minefields were expanded, each regiment received extra machine guns, and on 3 March also a battery of 75 mm howitzers. All the artillery in the beachhead – eight divisional battalions, the long-range 155 mm guns of a Marine defence battalion and 90 mm anti-aircraft guns – was directed by a single officer, General Leo Kreber. Six destroyers lay in the bay, and from the airfields flew Douglas SBD Dauntless dive-bombers and Avenger torpedo bombers of the 1st Marine Aircraft Wing, along with two New Zealand fighter squadrons. The one weakness of the defence was that the Japanese held the ridges, from which they could see almost the entire beachhead.

The assault on Hill 700

The bombardment of 8 March destroyed one B-24 bomber and three fighters on the Piva airfields and damaged nineteen aircraft. American observers – on the ground, in light aircraft and aboard the destroyers – quickly located the Japanese batteries, and the corps artillery replied with counter-battery fire. In the afternoon more than ninety dive-bombers and torpedo bombers attacked Hill 1111 and the neighbouring ridges. Before dusk all the bombers except six Avengers flew off to New Georgia, and for the rest of the battle the fighters left the beachhead every evening so as not to be destroyed on the ground.

Hill 700 dominated the whole beachhead. Its slopes had a gradient of 65–75 per cent, and the forward slope fell away so steeply that it could not be fully covered by machine-gun fire. It was defended by the 2nd Battalion of the 37th Division’s 145th Infantry Regiment, whose regimental commander was Colonel Cecil Whitcomb. As early as 6 March patrols reported large Japanese forces some 1,300 metres north of the hill, and on 7 March Japanese engineers appeared in front of the line, cutting the wire. Ammunition, two days’ rations and a can of water were stored in every bunker.

Some tens of minutes after midnight on 9 March, in torrential rain and fog, about two companies of the 23rd Regiment climbed the northern slope and attacked the platoon holding the saddle between the summit and a neighbouring rise. The Japanese seized several bunkers and drove a wedge into the American line. In the morning companies of the 1st and 2nd Battalions of the 145th Regiment counter-attacked and regained most of the ground; two M3 Stuart light tanks proved useless on so steep a slope. Japanese machine guns and mortars swept the supply route up the hill, and that day two destroyers fired some four hundred rounds at the positions supporting them.

At dawn on 10 March Iwasa’s group renewed the assault, but it collapsed under artillery fire. After a strike by 36 aircraft, the 145th Regiment counter-attacked at 5 p.m. and regained another strip of ground. On the night of 10–11 March the Japanese took only one bunker, and their morning attacks on 11 March were beaten off. General Beightler, dissatisfied that the regiment had still not restored its original line, sent the 2nd Battalion of the 148th Regiment up the hill and relieved Whitcomb, who had been found to be suffering from extreme combat exhaustion, of his command. After an artillery preparation the fresh battalion took one bunker after another and on 12 March restored the original defence line. On 13 March the remnants of Iwasa’s group began to withdraw. On the recaptured ground the Americans counted 309 bodies of Japanese soldiers and took two prisoners; the 37th Division lost 78 killed in this fighting.

Hill 260 and the creeks in the north

At the same time, at dawn on 10 March, Muda’s group attacked Hill 260 – a forward observation post of the Americal Division lying some 700 metres in front of the main line. It consisted of two knolls, which the Americans named North Knob and South Knob, joined by a narrow neck; an observation post had been built in a tree on the summit at a height of about 45 metres. The roughly eighty defenders lost the southern knoll in the first attack. Griswold ordered the hill to be held at all costs, although the division staff had previously not intended to defend it. Over the following days companies of the 182nd and 132nd Infantry Regiments with flamethrowers repeatedly fought their way onto South Knob and were pushed off it again; the corps staff rejected the division’s request for permission to withdraw. Finally the assistant division commander, General William McCulloch, abandoned frontal assaults and decided to bleed the defenders with artillery and flamethrowers. The Japanese did not abandon the hill until 27 March, and the Americans found 560 bodies on its summit. The fighting for Hill 260 cost the Americans 98 killed, 24 missing and 581 wounded – far more than the defence of Hill 700.

In the north, between 11 and 17 March, Magata’s group attacked the 129th Infantry Regiment several times in the area of Taylor’s Creek and Cox’s Creek. Each time it seized some of the bunkers, and the Americans retook them with the help of aircraft, bazookas, flamethrowers and tanks, including a platoon of M4 Shermans. The Japanese commanders then decided to gather all three groups in front of the 129th Regiment and attack together. The regrouping took almost a week. The attack by some 4,850 soldiers began after dark on 23 March, but the Americans, who knew the plan from captured documents, shattered the concentration with a hurricane of fire while it was still in its assembly areas. On the morning of 24 March a counter-attack by infantry and tanks, supported by seven artillery battalions, completely destroyed one battalion of the 45th Regiment and almost all of a battalion of the 53rd. On 25 March Hyakutake halted the offensive, and on 27 March he ordered a withdrawal to the starting positions. Fijian troops also took part in the last phase of the fighting and in the pursuit, as did Black soldiers of the 24th Infantry Regiment and the 93rd Infantry Division, who were committed to battle to gain experience.

Losses and assessments

Figures for Japanese losses vary widely. The American official history of 1959 gives more than 5,000 killed and more than 3,000 wounded. The Australian historian Karl James cites Japanese estimates of 3,500 killed and 5,500 wounded, many of whom later died of starvation and disease. Hiroyuki Shindō writes of about 2,700 killed among the soldiers directly engaged in the offensive and, in total – together with other units fighting on the island at the time – of 5,400 killed and 7,100 wounded. Several Japanese units had to be disbanded. According to the official history, XIV Corps lost 263 killed.

John Miller judged that the offensive had been lost at the planning stage: the Japanese had underestimated the enemy’s strength by half, and even had their estimates been correct, the troops and artillery they committed would not have sufficed to break a well-prepared defence. Concentrating all their forces at one point from the first day, instead of committing the groups one after another at intervals of several days, would have given them a chance of at least partial success. The US Navy historian Samuel Eliot Morison acknowledged that capturing the airfields would have cut “the most important link” in the Allied chain around Rabaul, but emphasised American superiority in the air and at sea. Shindō and another Japanese author, Kengorō Tanaka, argue on the other hand that the commanders of the 17th Army never really believed they could retake Bougainville – they wanted to strike while they still could, and in this way to “contribute” to the overall war situation.

Place in the war

The counter-offensive of March 1944 was the last major Japanese attack in the entire Solomon Islands campaign. It was fought at a time when Rabaul – the objective of the whole of Operation Cartwheel – had already been practically knocked out of the war: American aircraft had wiped out its planes and driven off its ships, and the landing on Los Negros on 29 February had begun to close the ring around the stronghold from the north-west. Had Hyakutake taken the Piva airfields, he would have dealt the Americans a painful blow and tied down their forces for a time, but – as Miller wrote – he would not have changed the course of the war.

After its defeat the 17th Army ceased to be a threat to the beachhead. Cut off from Rabaul, it was occupied mainly with survival: tending gardens, foraging for food in the jungle and fighting disease, which – according to most accounts – killed more of its soldiers in the following months than combat did. The base at Torokina grew to some 10 kilometres along the coast and 8 kilometres inland, and its stores and equipment made an enormous impression on the islanders. Until the end of 1944 the Americans confined themselves to patrolling and made no attempt to destroy the Japanese garrison. Between October and December 1944 they were relieved by General Stanley Savige’s Australian II Corps, while Griswold’s XIV Corps and the 37th Division sailed for the Philippines, where in 1945 they fought on Luzon and in Manila. The Australians, unlike the Americans, launched an offensive across the whole island; they fought the remnants of the 17th Army until August 1945.