Japanese reinforcements at Lae

On 7 January 1943 a Japanese convoy from Rabaul reached Lae on the north-east coast of New Guinea and, despite incessant attacks by Allied aircraft, put some 4,000 soldiers ashore. This was the detachment of Major General Tōru Okabe, infantry commander of the 51st Division, built around the 102nd Infantry Regiment. One transport sank on the way and another, badly damaged, was beached near Lae, but the objective had been achieved. Just as the fighting for Buna in Papua was dying down, the Japanese showed that they had no intention of giving up New Guinea. Lae and Salamaua, occupied without a fight in March 1942, were from then on to become their main line of defence on the island.

Under the date 23 January war chronologies also record that the Japanese, suffering setbacks in Papua, decided to continue the struggle and to mount sporadic air attacks on Allied forces in the region. Those decisions, however, had already been taken at the turn of December and January, and 23 January – the date American historiography takes as the end of the Papuan campaign – was rather the moment when their consequences became visible.

The Japanese decision at the turn of the year

By the end of 1942 the Japanese command had to face the fact that neither Guadalcanal nor the beachheads at Buna and Gona could be held. There was not enough shipping, warships were being lost on night-time supply runs, and the starving garrisons were wasting away from disease. On 31 December 1942 Emperor Hirohito approved the decision to withdraw from Guadalcanal, presented to him by the chiefs of the army and navy general staffs, General Hajime Sugiyama and Admiral Osami Nagano. At the beginning of January (sources give 3 or 4 January) Imperial General Headquarters sent new directives to the commands at Rabaul: evacuate Guadalcanal and the remnants of the troops in Papua, and in New Guinea hold and strengthen the area of Lae, Salamaua, Madang and Wewak. The weight of the Japanese effort in the South-West Pacific was shifting from the Solomon Islands to New Guinea.

Responsibility for these operations lay with Lieutenant General Hitoshi Imamura, commander since November 1942 of the Eighth Area Army at Rabaul, to whom Lieutenant General Hatazō Adachi’s Eighteenth Army was subordinate. Imamura read his opponent’s intentions correctly. In the mountains west of Lae and Salamaua the Australians kept a small detachment, Kanga Force, based on the airfield at Wau, a former gold-rush town. From there they could threaten both Japanese bases. On 29 December, therefore, Adachi ordered Okabe to cross from Rabaul to Lae and immediately strike inland to capture Wau.

At the same time the Japanese command began moving new divisions to New Guinea: the 20th Division from Korea and the 41st Division from China. The first landed at Wewak on 19 January, the second in February.

A convoy under air attack

The Allies knew about the Japanese preparations. Ultra codebreakers were reading Japanese shipping codes, and by 3 January at the latest General Douglas MacArthur’s headquarters knew that a troop convoy would sail from Rabaul to Lae, though not its final destination. The commander of the land forces, the Australian General Thomas Blamey, did not wait for clarification: on 4 January he ordered the 17th Infantry Brigade to be moved from Milne Bay to Wau.

The commander of the Allied air forces in the South-West Pacific, General George Kenney, wanted to smash the convoy while it was still in port. He ordered his bomber commander, Brigadier General Kenneth Walker, to strike Rabaul at dawn. Walker considered a night take-off from Port Moresby too risky and on 5 January led six B-17s and six B-24s over the harbour at noon. The crews reported hits on nine ships; post-war research confirmed the sinking of one freighter and damage to several vessels. Two bombers failed to return, among them the aircraft carrying Walker. The general was killed and was posthumously awarded the Medal of Honor.

On 5 or 6 January – studies give both dates – five transports escorted by five destroyers left Rabaul along the south coast of New Britain. They were shielded by low cloud and Japanese fighters. American and Australian aircraft tracked the convoy down and attacked it for two days. At night a Catalina flying boat of No. 11 Squadron RAAF sank the transport Nichiryu Maru. The destroyers rescued 739 of the roughly 1,100 soldiers on board, but all the Okabe Detachment’s medical supplies went to the bottom – a loss that would take its revenge in the jungle. On 7 January the convoy entered Lae and began unloading. B-25 bombers damaged the transport Myoko Maru so badly off Lae that she had to be beached.

In all, Allied aircraft flew 416 sorties against the convoy. They claimed 69 Japanese aircraft shot down for the loss of 10 of their own; like most air combat claims of the time, these figures were probably inflated. The P-38 fighter pilot Lieutenant Richard Bong, later the highest-scoring American ace of the war, claimed further victories in these days and became an ace. For the Allies, however, the outcome was disappointing: two ships lost, several damaged, and some 4,000 soldiers ashore. Kenney and his staff concluded that high-altitude bombing was not enough against manoeuvring ships. They began training crews in low-level attacks and skip bombing.

The race for Wau

Okabe did not stop at Lae. Between 10 and 16 January his detachment moved by barge along the coast to Salamaua, from where it set off into the mountains. To conceal his strength and objective from Allied aircraft, he chose an old, little-used track through dense jungle, running parallel to the main route to Wau. The soldiers carried food, ammunition and equipment on their backs; the march took longer than planned, and supplies dwindled.

Meanwhile the Australians were racing against time. The battalions of the 17th Brigade were shipped from Milne Bay to Port Moresby, from where they were to reach Wau by transport aircraft – the only practical route across the mountains. Aircraft could land on the airfield in the Wau valley only in good weather, and cloud in the mountains often closed the way. The outcome was to be decided at the end of January.

23 January: the end in Papua, a new line of defence

On 22 January organised Japanese resistance ceased at Sanananda, their last beachhead on the north coast of Papua, and 23 January is regarded as the end of the Papuan campaign. The fall of Gona and Buna in December and the capture of Buna Government Station on 2 January had brought to a close the fighting for Buna and Gona and the whole half-year struggle for Papua, which had begun with the Japanese landing near Buna in July 1942 and the march over the mountains along the Kokoda Track. Some of the survivors from Papua – several thousand men, according to some studies – made their way by barge and on foot along the coast to the Lae and Salamaua area, where they reinforced the garrisons there.

The Japanese decision at the turn of the year thus meant a change of line, not an abandonment of the fight. By giving up Papua and Guadalcanal, Imperial General Headquarters hoped to halt the Allies on the north coast of New Guinea and in the central Solomons, and so protect Rabaul. The army and navy air arms were to support this defence with raids on Allied bases and airfields – but in January and February these raids were small and irregular. The Japanese air units, bled white over Guadalcanal, lacked experienced crews and aircraft, while Kenney’s air force, reinforced in those weeks with new transport aircraft and fighters, was winning air superiority over New Guinea.

Place in the history of the war

The landing at Lae was the last successful Japanese troop movement to New Guinea on such a scale. Okabe’s attack on Wau, launched on 29 January, was repulsed in the Battle of Wau, which lasted several days, thanks to reinforcements flown in at the last minute; by 4 February the Japanese had withdrawn towards Mubo and Salamaua. The next, larger convoy, carrying the main body of the 51st Division and sent from Rabaul to Lae at the beginning of March 1943, was destroyed in the Battle of the Bismarck Sea by aircraft using precisely the low-level attacks whose necessity the January convoy had demonstrated. Only about 1,200 of nearly 7,000 soldiers reached Lae.

The Japanese never again managed to reinforce Lae and Salamaua effectively by sea. In April 1943 Admiral Isoroku Yamamoto threw naval aviation into an air offensive against Allied bases in New Guinea and the Solomon Islands – much larger than the January raids, but also ineffective. In September 1943 the Australians, supported by American paratroopers and an amphibious landing, captured Salamaua and Lae. The January convoy delayed that moment by several months but did not reverse the course of the war in New Guinea: after the defeat in Papua the initiative already lay with MacArthur.