This was the US seizure of Sansapor and Mar on the Vogelkop peninsula at the western tip of Japanese-occupied Netherlands New Guinea, marking the end of the campaign of General Douglas MacArthur’s South-West Pacific Area command along the north coast of New Guinea (30 July/31 August 1944).
During the spring of 1944, the approach of the war to the Netherlands East Indies, which was the strategic and economic heart of Japan’s so-called Southern Resources Area, was signalled by a number of events including, in the west, the ‘Cockpit’ carrierborne air attack on Sabang off the north coast of Sumatra by the British Eastern Fleet on 19 April and in the east, on 22 April, the ‘Reckless’ landing of US forces from eastern New Guinea at Hollandia on the north coast of Dutch New Guinea.
Field Marshal Count Hisaichi Terauchi’s Southern Expeditionary Army Group, headquartered in Saigon in occupied French Indo-China, was responsible for the defence of the East Indies and Philippine island groups. Under the Southern Expeditionary Army Group, Lieutenant General Kumakashi Harada’s 16th Army, headquartered at Batavia (now Djakarta) on Java, controlled all the Japanese army occupation forces in the East Indies until January 1943. Japanese efforts to reinforce the East Indies and thus to create a new ‘absolute zone of national defence’ began in the autumn of 1943. Within the major reorganisation that this resulted, two major headquarters were transferred from Manchukuo to the East Indies. The Japanese forces in all of the East Indies, except Sumatra, were controlled of General Korechika Anami’s 2nd Area Army, which was initially headquartered from 23 November 1943 at Davao on the island of Mindanao in the occupied Philippine islands group: on 1 December this area army controlled Lieutenant General Fusataro Teshima’s 2nd Army, Lieutenant General Hatazo Adachi’s 18th Army and Lieutenant General Nobumasa Tominaga’s (from 15 October 1943 Lieutenant General Kenzo Kitano’s 19th Army possessing, between them, 170,000 men, along with Lieutenant General Einosuke Sudo’s 7th Air Division, which was created in January 1943. The 7th Air Division was initially based on Amboina, but was released to the 8th Area Army to operate in May and June 1943 in eastern New Guinea, which the Japanese designated at the North Australia Front.
Redeployed from Manchukuo, Teshima’s 2nd Army was headquartered at Manokwari (occupied by the Japanese on 12 April 1942) on the north-western shoulder of Geelvink Bay, and was responsible for north-western Dutch New Guinea to the west of 140° E and to the north of the Sneeuw mountains. It had 50,000 men and was assigned, in order of their arrival, Lieutenant General Hachiro Tagami’s 36th Division, Lieutenant General Yoshio Ishii’s 32nd Division and Lieutenant General Shunkichi Ikeda’s 35th Division. The 36th Division comprised the 222nd, 223rd and 224th Regiments, and arrived from China in December 1943. It was positioned at Wakde Island and Sarmi on the north-central coast of Dutch New Guinea. The 222nd Regiment (Biak Detachment) defended Biak Island in the northern opening of Geelvink Bay. The 32nd Division and 35th Division were also deployed from China and suffered severe losses in personnel and equipment as a result of air and submarine attack en route to the East Indies.
The 32nd Division comprised the 210th, 211th, 212th Regiments and the 32nd Field Artillery Regiment, and while on passage to Halmahera lost almost half of its infantry and artillery. Arriving early in May 1944 the division became responsible for the defence of Halmahera and other islands in the Moluccas group.
The 35th Division comprised the 219th Regiment, 220th Regiment, 221st Regiment and 4th Independent Mountain Artillery Regiment. The division was deployed to Dutch New Guinea via the Philippine islands group and Halmahera island and, arriving late in May and early in June 1944, became responsible for for the defence of Manokwari and Sorong.
(Before the arrival of the 32nd Division and 35th Division, first the 3rd Division and then the 14th Division had been earmarked for movement from China, but could not be released as a result of developments in that theatre.)
Other elements controlled by the 2nd Army included the 1st Field Base Unit and 2nd Field Base Unit located on Halmahera and at Monokwari respectively. Major General Shinichi Endo’s 57th Independent Mixed Brigade arrived from Japan during October 1943 at Menado to garrison the northern part of Celebes island.
Lieutenant General Kenzo Kitano’s 19th Army was created on 7 January 1943 with 50,000 men and was responsible for the south-western area of Dutch New Guinea, the Aroe, Kai, and Tanimbar islands to the south and south-west of New Guinea, Ceram and Boeroe islands to the west, Timor island, and the Lesser Sunda islands group.
This left the 16th Army responsible only for the defence of Java and Madoera. The 16th Army’s 5th Division and 48th Division, commanded by Lieutenant Generals Seiichi Yamada and Yuitsu Tsuchihashi respectively, were transferred to the 19th Army, which had its headquarters on Amboina. Later commanded by Lieutenant General Kunitaro Yamada, the 48th Division continued to garrison Timor with its headquarters at Koepang. Early in 1944 Seiichi Yamada’s 5th Division was moved from Amboina to garrison the Kai, Aroe, and Tanimbar islands with its headquarters on the first of these, as well as Modowi and Mimika on the western end of Dutch New Guinea’s southern coast. Lieutenant General Tadaichi Wakamatsu’s (from 14 November 1944 Lieutenant General Shishichiro Kokubu’s) 46th Division (123rd Regiment and 147th Regiment but not its 145th Regiment retained in the Bonin islands group) arrived from Japan early in 1944 to garrison the Lesser Sunda islands group, but in August 1945 was redeployed to Malaya.
Vice Admiral Gunichi Mikawa’s (from 18 June 1944 Vice Admiral Shiro Kawase’s 2nd Southern Expeditionary Fleet was based at Soerabaja in Java. Under it were the 21st Special Base Force at the same location, the 22nd Special Base Force at Balikpapan on Borneo, the 23rd Special Base Force at Macassar on Celebes, and the 24th Special Base Force at Ende on Flores island.
Vice Admiral Seigo Yamagata’s 4th Southern Expeditionary Fleet was headquartered at Amboina with the 25th Special Base Force at Kaimana on the southern side of the Dutch New Guinea’s western tail, the 26th Special Base Force at Kau Bay on Halmahera, the 27th Special Base Force at Wewak in North-East New Guinea, and the 28th Special Base Force at Manokwari on the north-west shoulder of Geelvink Bay.
The 2nd Guard Force was on Tarakan island in Dutch Borneo, the 3rd Guard Force on Bali island, the 5th Guard Force at Hollandia in New Guinea, and 20th Guard Force on Amboina island. The 23rd Air Flotilla was based at Kendari on the south-eastern peninsula of Celebes island.
The Vogelkop peninsula extends to the north-west off the western end of Netherlands New Guinea’s tail, and here the Japanese held positions at Manokwari on the north-east corner, the small island of Sorong off the western end, Babo on the south coast of McCluer Gulf, and Nabire on the southern end of Geelvink Bay.
MacArthur’s South-West Pacific Area staff proposed several objectives on the Vogelkop peninsula on which airfields could be established to support subsequent operations via Halmahera toward the Philippine islands group: Mindanao island lies some 600 miles (965 km) to the north-west. The US planners felt that it was desirable to have airfields between Noemfoor to the east and the future objective of Morotai island to the north-west. However, as the tactical and strategic situations changed, these early plans were cancelled. One of the main plans was to capture Sorong and Waigeo, the latter a much larger island some 60 miles (100 km) to the north-west of the former.
Another operation, for which a major preparatory effort had begun in the USA, was the capture and development of the Klamono oilfields some 30 miles (50 km) inland from Sorong island, and to this end the creation of the 5,000-man Engineer Petroleum Production Depot had been started in California. It was planned that this organisation would move to and operate the Klamono oilfields for in-theatre supply of fuel oil to ships. Its oil required little refining before it could be burned by ships. The effort’s manning, shipping and support requirements were found to be more demanding than simply shipping the fuel from the USA, so the project was cancelled.
A new plan was then created to take and hold an enclave on the north central coast of the Vogelkop peninsula in an area unoccupied by the Japanese, and for this the area of Sansapor and Mar was selected, and this lies on the north-western coast of the Vogelkop peninsula some 18 miles (29 km) to the south-west of Kaap de Goede Hoop (otherwise Cape Jamersba), the peninsula’s northernmost point. Sorong is 65 miles (105 km) to the south-west and Manokwari 140 miles (225 km) to the east.
In June 1044, Sansapor was a small village and copra plantation on the Vogelkop peninsula. MacArthur desired an airfield in or near the Vogelkop peninsula to cover his forces' next leap to Halmahera island, but aerial reconnaissance had determined by 17 June that there were no suitable sites at Waigeo, the initial choice of MacArthur’s staff. A scouting party had already been dispatched in the submarine S-47 and was diverted to the Sansapor area, arriving on 23 June and spending a week in the area. The scouting party reported that there were good landing beaches and airfield sites on the coastal plain. The nearest Japanese force was a group of about 100 men at a barge station at Sansapor village.
The terrain at Sansapor comprises a narrow, swampy coastal plain overlooked by steep hills rising to the 4,300-ft (1310-m) Mt Tonkier, some 12 miles (19.25 km) inland. The dominant terrain feature in the immediate area is the 350-ft (107-m) Mt Sowewe. The higher ground was covered with light scrub or jungle growth.
Thus US reconnaissance had established that the area possessed good landing beaches and sites suitable for the construction of airfields. The area to be taken between Cape Sansapor in the west and Cape Opmarai in the east was about 12 miles (19.25 km) wide, and about 14 miles (22.5 km) farther south-west of Cape Sansapor, was Mega Bay where a later landing would take place. Roughly in the assault area was the village of Mar (otherwise Warsai) on the eastern side of the swampy mouth of the Wewe river. Inland was more swamp stretching from either bank of the river. The Japanese operated a small barge-staging base at Cape Sansapor on the route linking Sorong and Manokwari, and US intelligence believed that this was manned by no more than 100 sea transport troops. Aerial reconnaissance detected open strips near the mouth of the Wewe river, which might indicate initial clearing of an airstrip, and that if this was in fact the case there could be an airfield construction unit, of up to 700 men, in the area.
Further ground reconnaissance in mid-June 1944 determined that airfields could be constructed near Mar and on Middelburg island of the Soe islands group just to the north of Mar. No Japanese were found in the immediate area, and it was discovered that the previously detected cleared strips were not preparations for airfield construction but rather overgrown, abandoned native gardens.
Ordered by MacArthur on 4 July, the 'Globetrotter' operation was undertaken by parts of Major General Franklin C. Sibert’s 6th Division (1st, 20th and 63rd Infantry) remaining in the area of Wakde and Sarmi after ‘Straightline’. Organised as Task Force ‘Typhoon’ with additional engineer elements for the construction of airfields, this element of Vice Admiral Thomas C. Kinkaid’s 7th Fleet (7th Amphibious Force) was Rear Admiral Daniel E. Barbey’s Task Force 77.
From 27 July, aircraft of Lieutenant General George C. Kenney’s US 5th AAF attacked the airfields on the Vogelkop and Halmahera island in order to neutralise the possibility of Japanese air opposition.
The troops were transported from Maffin Bay, near Wakde, by Rear Admiral William M. Fechteler’s TF77.2 (Attack Group), which had departed on 27 July with Fechteler flying his flag in the destroyer Swenson and otherwise comprising the troop-carrying destroyer conversions Herbert, Kilty, Ward, Crosby, Dickerson and Schley, 19 infantry landing craft of which three were equipped to fire rockets, eight tank landing ships, four patrol craft and one tug, all escorted by the destroyers Stevenson, Stockton, Welles, Radford, Hobby, Nicholson, Wilkes, Grayson, Gillespie, La Vallette and Jenkins.
The operation was covered by Rear Admiral Russell S. Berkey’s TF78, which at full strength comprised Rear Admiral V. A. C. Crutchley’s Australian TF74 (Covering Group 'A') with the heavy cruisers Australia and Shropshire, and the destroyers Warramunga, Arunta and US Ammen and Mullany; and Berkey’s own US TF75 (Covering Force 'B') with the light cruisers Phoenix, Nashville and Boise, and the destroyers Hutchins, Bache, Daly, Abner Read and Bush (Destroyer Squadron 24).
Air patrol, reconnaissance and support was the task of TF73 (Aircraft 7th Fleet) comprising Task Group 73.1 (Seeadler Harbor Group) with the seaplane tenders Tangier and Heron and small seaplane tender San Pablo supporting VP-33’s 13 Consolidated PBY-5 flying boats, VP-52’s 13 PBY-5 machines and VB-106’s 11 Consolidated PB4Y-1 Liberator machines, and TG73.2 (Langemak Bay Group) with the small seaplane tender Half Moon supporting VP-34’s 10 PBY-5 machines.
The lack of Japanese air activity persuaded Sibert and Fechteler that their forces were in a position to achieve complete tactical surprise, and thus there was no preliminary bombardment. US, Australian and Dutch aircraft instead raided Manokwari, Sorong, Halmahera, Ceram and Amboina islands farther to the west. The two commanders' assessment proved correct: when men of the 1st Infantry landed just to the east of Mar at 07.30 on 30 July, there was no sign of the Japanese, although three Japanese were located and killed later on this first day. To the north-east of Mar, Middelburg and the neighbouring Amsterdam islands were also occupied, again without opposition, from 07.30 and 11.30 respectively by troops delivered in amphibian tractors.
The Red beach at Mar provided good landing sites for tank landing ships, but the very soft beach sand slowed wheeled vehicle movement and the jungle behind the beach allowed for only limited dump and assembly areas. Units moved inland and established a beach-head line 800 yards (730 m) deep before the fall of night.
On 31 July the 3/1st Infantry Battalion Landing Team boarded landing craft at the mouth of the Wewe river and 08.45 landed over Green beach on Cape Sansapor to the west of Mar. There was no opposition and it was apparent that the Japanese had hastily abandoned their barge-staging base. The beach-head was expanded inland as much as 8 miles (13 km) and along the coast to the Koor river in the area to the east of Cape Opmarai and the Sekowa river to the south-west of Cape Sansapor, a distance of some 30 miles (48 km). Work had begun immediately on airfields between the initial landing point and the Wewe river, and also on Middelburg island. Patrols were sent out, and on 3 August 110 sick and wounded Japanese were captured at a crude hospital near Cape Opmarai.
During the fighting on Biak island during May and June, Ikeda’s 35th Division located at Sorong and Halmahera had started to move by sea to Manokwari, from which it was to stage along the coast to reinforce Biak in ‘Kon’. Much of the division was now at Manokwari, which was attacked ever more heavily by Allied aircraft from Wakde, Biak and Noemfoor. Many of the ration dumps were destroyed, and as a result the 12,000 to 15,000 troops there could no longer be supported. Even with Sorong only 65 miles (105 km) distant from Sansapor, the 35th Division and 2nd Amphibious Brigade could not consider offensive action because of a lack of water transport and the impracticality of overland movement because of the impossibility of carrying sufficient supplies and ammunition.
Teshima’s 2nd Army at Manokwari ordered the 35th Division to return to Sorong by foot beginning in early July, and the headquarters of the 2nd Army itself embarked on an overland move of 150 miles (240 km) to the south to Windehsi at the point at which the isthmus of the Vogelkop peninsula joins the mainland. Major General Yuuki Fukahori’s 1st Independent Mixed Brigade, assembled largely from the 2nd Field Base Unit and the 28th Special Base Force, remained at Manokwari.
On 15 August the 6th Division was warned that elements of the 35th Division were moving west inland of the US beach-head, and the US division therefore increased its patrol activity inland of the beach-head and established ambushes to interdict the Japanese. Elements of the 1st Infantry were landed briefly at Mega Bay some 30 miles (48 km) to the south-west of Mar on 18 August to search for Japanese units which had escaped past Mar and Sansapor, and on 23/25 August the 20th Infantry arrived at Mar to rejoin its parent division. At that time Sibert passed command of the division and the task force to Brigadier General Charles E. Hurdis as he departed to assume command of the X Corps.
The Japanese flew light bombing raids against the US positions on 25, 27 and 31 August, and by the end of the month the 6th Division had killed 385 Japanese and taken prisoner another 215, many of the latter Formosans. Most of the 35th Division managed to reach Sorong, but the mere presence of the 6th Division forced the Japanese troops, weakened by illness and hunger, to divert to the south through more rugged country, where large numbers died. The US losses between 30 July and 31 August were 14 dead, 35 wounded and nine injured. More than 800 men were diagnosed with scrub typhus or fever of unknown origin, and of these nine died.
The 5,400-ft (1645-m) airfield on Middelburg island was declared operational for fighters on 17 August, while the 6,000-ft (1830-m) airfield at Mar, which was intended for medium bombers, became operational on 3 September and was soon extended to 7,500 ft (2285 m). These airfields supported the ‘Tradewind’ operation against Morotai island, and interdiction operations were flown from them throughout the Molucca islands. A small PT-boat base was built on Amsterdam island early in August.
The 6th Division remained in the area of Sansapor and Cape Opmarai until departing for service in the Philippine islands campaign in December 1944.
The Japanese forces remaining on the Vogelkop peninsula at this time were the 2nd Army, 35th Division, 1st Independent Mixed Brigade and 2nd Amphibious Brigade, which were all isolated from the rest of General Korechika Anami’s 2nd Area Army on Halmahera, Ceram and Celebes islands, and incapable of mounting any offensive action for lack of supplies as well as air and navy support. The headquarters of the 2nd Army was later evacuated to Celebes island.
The primary US formation of the New Guinea campaign was Lieutenant General Robert L. Eichelberger’s I Corps of Lieutenant General Walter C. Krueger’s 6th Army, whose experience and capable forces made possible a series of combined operations in which land, sea and air forces co-operated perfectly to identify key points in the Japanese defences for sudden assault and destruction.
By the time ‘Globetrotter’ had been undertaken, MacArthur was well advanced in his planning for the steps that would now take his forces back to the Philippine islands group in the confidence that there was no realistic threat to his rear in New Guinea, for though the 2nd Area Army still had some 120,000 men under arms in this vast island and on neighbouring Timor island, these forces (Yamada’s 5th Division, Ishii’s 32nd Division, Ikeda’s 35th Division, Tagami’s 36th Division, Wakamatsu’s 46th Division, Tsuchihashi’s 48th Division and Sudo’s 7th Air Division) of the 2nd Army and Adachi’s 18th Army were so scattered and demoralised that they could not offer any cohesive threat to the Allies as they were pressured constantly by Australian and US forces.
Isolated in New Guinea and Timor without chance of reinforcement or adequate resupply, the Japanese were thus condemned to wait out the war in conditions of increasing malnutrition and disease. It had taken MacArthur’s forces six months to clear the Japanese from Papua, and nine months to drive the Japanese from North-East New Guinea and isolate the Japanese base area on New Britain and New Ireland. Yet MacArthur’s bold ‘coast-hopping’ campaign along the western half of New Guinea had taken only three months and left the US forces poised for a return to the Philippine islands as soon as the northern island of Morotai island in the Molucca islands group had been taken in ‘Tradewind’.