The capture of Manus

Before dawn on 15 March 1944 an LST landing ship left Salami plantation on Los Negros and headed across Seeadler Harbour towards Manus, the largest of the Admiralty Islands. On board were troops of the 8th Cavalry Regiment, and in its hold were LVT amphibious tracked carriers. After a short but violent preparatory bombardment, troopers of the 2nd Brigade of the 1st Cavalry Division came ashore near Lugos Mission, some four kilometres west of the settlement of Lorengau. This was the start of the last major stage of the fighting for the archipelago, which had begun two weeks earlier with the landing on Los Negros.

Under 15 March it is often recorded briefly that on that day “the Americans captured Manus Island”. That is a simplification: on 15 March the troops merely landed on the island. The airfield near Lorengau was taken on 17 March and the settlement itself on 18 March, and organised resistance by the Japanese garrison on Manus ended only around 25 March, after six days of fighting around the village of Rossum in the interior. Scattered groups of Japanese soldiers went on hiding in the jungle for many weeks afterwards.

After Los Negros

At the beginning of March the fighting on Los Negros, where a thousand of General Douglas MacArthur’s cavalrymen had landed on 29 February, moved into a mopping-up phase. Colonel Yoshio Ezaki’s night counter-attacks were beaten off, on 5 March the commander of the 1st Cavalry Division, Major General Innis P. Swift, took command, and on 9 March the first Kittyhawk fighters of No. 76 Squadron RAAF landed at Momote airfield. Seeadler Harbour, the enormous natural anchorage between Los Negros and Manus, had been open to Allied ships since 8 March, although Japanese guns on the islets at its entrance still had to be silenced.

The real prize, however, was Manus. According to American reconnaissance, some 2,700 Japanese soldiers and sailors remained on it. Lorengau, the only settlement resembling a small town, had an airfield and a junction of four roads and – as the Americans knew – was strongly fortified. Swift decided not to attack it head-on, but to land Brigadier General Verne D. Mudge’s 2nd Brigade on the beaches near Lugos, where the Japanese were not expecting a landing, and to strike at Lorengau from the west.

Hauwei – a bloody prelude

The landing needed artillery cover, and guns on Los Negros could not reach far into Manus. On 11 March, therefore, three patrols set out in landing craft to look for firing positions on the offshore islets. Two returned without incident: Bear Point turned out to be free of the enemy, and good gun sites were found on the Butjo Luo islets. The third patrol – 25 men of the 302nd Cavalry Reconnaissance Troop, two artillery officers, an Australian guide from the ANGAU administrative unit and a local guide, Kaihu, from the village of Mokerang – sailed to the islet of Hauwei.

As the soldiers were coming ashore, Major Carter S. Vaden spotted a camouflaged bunker and threw two grenades into it. At that very moment hidden Japanese mortars and machine guns opened fire. The covering PT boat was hit and withdrew, and the landing craft, which twice went back under fire for survivors, was holed by a mortar round and sank. After three hours the survivors were picked up from the water by another PT boat, covered by the Australian destroyer HMAS Arunta. Eight Americans were killed, among them Vaden, and fifteen were wounded. Kaihu, who had been posted missing, swam back to Los Negros.

Swift postponed the landing at Lugos and on 12 March sent the 2nd Squadron of the 7th Cavalry Regiment against Hauwei, preceded by fire from four destroyers, rockets launched from barges, artillery on Los Negros and the bombs of Australian Kittyhawks. The Japanese – sailors in excellently sited bunkers with interlocking fields of fire – resisted fiercely. Their resistance was broken only by a medium tank brought over by barge the following day; the cavalry lost eight killed and 46 wounded, and 43 Japanese dead were counted. Three field artillery battalions were moved to Hauwei and Butjo Luo, from where they could now reach Lorengau.

The landing at Lugos

On the morning of 15 March the Lugos area was shelled by four American destroyers, rocket barges and the artillery on the islets, while 18 B-25 bombers dropped 81 bombs and strafed the shore. The first two squadrons of the 8th Cavalry, carried in LVTs, met only weak resistance: the Japanese had not expected a landing there, and their few positions above the beach were quickly overrun. The LST went back for a further echelon and brought the 7th Cavalry Regiment, which took over the defence of the beachhead.

The 1st Squadron of the 8th Cavalry set off eastwards along the coast but was halted by a complex of bunkers on the edge of Lorengau airfield. After an artillery barrage and a strike by Kittyhawks, the troopers occupied without a fight a ridge overlooking the runway. The first attack on the airfield itself, however, stalled in front of a further line of log-and-earth bunkers that withstood artillery fire.

Lorengau and Rossum

On 17 March, reinforced by the 1st Squadron of the 7th Cavalry and by tanks, the Americans renewed the attack and took the airfield. The next day, 18 March, they occupied Lorengau – the pre-war seat of the Australian administration of the Manus district in the mandated Territory of New Guinea.

The main Japanese forces on Manus, however, had still not been found. The 7th Cavalry came upon them only on 20 March, while advancing inland towards the village of Rossum. For six days the two cavalry regiments took one position after another, smashing bunker after bunker with artillery, mortars and grenades. Around 25 March organised resistance on Manus came to an end. On 24 March, at Papitalai on Los Negros, the last group of that island’s defenders, about fifty strong, was wiped out.

Hunger in the mountains

The surviving Japanese retreated into the mountains without food or ammunition. A diary found on a dead soldier conveys their situation. On 28 March its author wrote that about 300 men were left of his unit and that their lives were “numbered in days”. On 30 March: “This is the eighth day since we began the retreat. We wander along mountain roads because of the enemy. (…) We have eaten all our rations. Our bodies are growing weaker, and the hunger is becoming unbearable.” On 1 April: “According to a report, our troops at Lorengau must withdraw. From now on there is nothing left but to live as the natives live.”

Smaller islands still remained. On 30 March the 1st Squadron of the 7th Cavalry landed on Pityilu and after a fight destroyed the post there. On 1 April troopers of the 12th Cavalry Regiment crossed to the islets of Ndrilo and Koruniat – as historians of the campaign point out, this was probably the only amphibious operation by American troops in the war carried out in native canoes. On 3 April Rambutyo island was taken. Before each of these landings ANGAU men discreetly evacuated the inhabitants to spare them the bombardment. Patrols, often guided by local informants, hunted down stragglers until the campaign was formally declared over on 18 May 1944.

According to the final report of General Walter Krueger, in the whole Admiralty Islands campaign 3,280 Japanese dead were counted, 75 were taken prisoner and about 1,100 disappeared without trace. The Americans lost 326 killed, 1,189 wounded and 4 missing. The Australian administration also recorded casualties among the local population: several killed in the fighting and by the Japanese, and 20 killed and 34 wounded accidentally by Allied bombs and shells.

A harbour for a whole fleet

Even before the fighting had died down, Seabees – the US Navy’s construction engineers – began arriving on Manus and Los Negros. A dispute over who should control the base set MacArthur against Admiral Chester Nimitz, who proposed moving the boundary of the South Pacific Area so that it would take in the Admiralties. The Joint Chiefs of Staff rejected the idea, and on 3 March MacArthur and Admiral William Halsey reached a compromise in Brisbane: the base was to serve the entire US fleet.

Within a few months the hitherto empty islands acquired two airfields for heavy bombers – an enlarged Momote and a new one at Mokerang – carrier aircraft bases on Ponam and Pityilu, tanks for hundreds of thousands of barrels of fuel, workshops and floating docks at Lombrum, a hospital, depots and a recreation centre for ten thousand sailors at a time. On 18 April B-24 bombers flew in to Momote, and two days later they attacked Woleai atoll in the Carolines.

Place in the war

The capture of Manus closed the ring around Rabaul from the west. When the Marines landed unopposed on Emirau, north of New Ireland, on 20 March, some hundred thousand Japanese soldiers and sailors on New Britain and New Ireland were cut off and played no significant part for the rest of the war. The Allies did not have to storm either Rabaul or Kavieng, and MacArthur gained a forward harbour that enabled him to leap hundreds of kilometres along the coast of New Guinea. Japanese Imperial Headquarters regarded the loss of the Admiralties as the loss of the entire forward defence line and ordered a new one to be built in western New Guinea.

In April 1944 the forces for the landings at Hollandia and Aitape assembled in Seeadler Harbour, and in the autumn part of the fleet that carried MacArthur’s troops to Leyte and fought the Battle of Leyte Gulf sailed from here. In 1945 Manus was the forward base of the British Pacific Fleet. Seeadler Harbour, which the Japanese had never managed to put to real use, became for the Allies one of the most important harbours of the Pacific war.