The Sixth Army's landing at Lingayen Gulf on 9 January had come as no strategic surprise to General Tomoyuki Yamashita, commander of the Japanese 14th Area Army in the Philippines.1 The landing had achieved tactical surprise, for Yamashita had not expected the invasion for at least another two weeks, and 14th Area Army planners had not seriously considered the possibility that the Sixth Army would land its main strength across Lingayen Gulf's southern shores. But Yamashita knew an invasion was coming, expected it through Lingayen Gulf, and, ever since the invasion of Mindoro, had been redoubling his efforts to prepare for the inevitable.
Japanese Strategy in the Philippines
Originally, Japanese plans for the defense of the Philippines had envisaged that the decisive battle would be fought on Luzon.2 Air and naval forces might seek their Armageddon in the central or southern Philippines, but the 14th Area Army would undertake only delaying actions there.
The Allied invasion of the central Philippines at Leyte in October precipitated a switch, and the Japanese decided to fight it out on the ground at Leyte. Leyte turned into a graveyard of Japanese hopes. Their Navy suffered a shattering defeat; they lost hundreds of land-based and carrier-based aircraft, losses they could ill afford; they threw away ground
reinforcements drained from China and Luzon; their loss of cargo ships and transports was irreplaceable.3
Yamashita had steadfastly opposed making Leyte a decisive battle area and, able tactician that he was, had concluded as early as the first week of November that Leyte was lost. At that time he had proposed to his immediate superior, Field Marshal Count Hisaichi Terauchi of Southern Army, that the Leyte fight be halted and efforts be concentrated upon preparing the defenses of Luzon. Terauchi turned deaf ears to this proposal as he did to a similar Yamashita plan in early December after an Allied force had landed on the west coast of Leyte, closing the 14th Area Army's principal port of entry on that island.
Next, Yamashita viewed the Allied invasion of Mindoro as an event that provided him with a welcome opportunity to cease his all but impossible efforts to reinforce Leyte. Calling off--apparently on his own initiative--a last reinforcement attempt, Yamashita again recommended to Count Terauchi that attention be turned to Luzon. The latter, having already forestalled Yamashita's earlier attempts to halt the fighting on Leyte, now directed the 14th Area Army to prepare a counterattack against Mindoro.
This Yamashita had no intention of doing. It was therefore with some uneasiness that he greeted Lt. Gen. Jo Iimura, the Chief of Staff of Southern Army, when the latter arrived at Manila from Saigon--site of Terauchi's headquarters--on 17 December. But Iimura, after talking to Yamashita, advised Terauchi that the 14th Area Army commander's recommendations ought to be followed. On the 19th, Terauchi finally ordered Yamashita to prepare the defenses of Luzon. The idea of sending strong reinforcements to Mindoro was quietly dropped, and the Japanese 35th Army on Leyte was informed that it could expect no more help. On 25 December Yamashita directed Lt. Gen. Sosaku Suzuki, 35th Army commander, to evacuate his forces from Leyte as best he could and make preparations to defend the rest of the southern and central Philippines.4
Yamashita's planning problems were still not solved. On 21 December Lt. Gen. Shuichi Miyazaki, Chief of Operations, Army Section, Imperial General Headquarters, reached Manila prepared to direct Yamashita to continue defensive efforts in the central Philippines and simultaneously ready the defenses of Luzon. After two days of conferences with Iimura, Yamashita, and the latter's chief of staff, Lt. Gen. Akira Muto, Miyazaki also decided that Yamashita's plans had to be followed. Miyazaki concluded that no one in Tokyo had enough knowledge of the situation in the Philippines to overrule Yamashita, and he promised Yamashita to do his best to prevent any further interference by Imperial General Headquarters with the conduct of operations on Luzon. Yamashita, belatedly, had his way.5
The Japanese on Luzon
During the first half of November Yamashita, while trying to convince Southern Army of the folly of continuing the fight on Leyte, had prepared a draft plan for the defense of Luzon. A realist, Yamashita knew that if it had not already done so, Imperial General Headquarters would soon write Luzon off as a strategic loss. He believed, therefore, that operations on Luzon would have to be primarily defensive in character, and he knew that he could expect no reinforcements once an Allied invasion force reached the island. Nevertheless, his November plans included provisions for a strong counterattack against an Allied landing force--a counterattack that would be executed only if expected supplies and equipment reached Luzon, if he could keep on the island three infantry divisions scheduled for shipment to Leyte, if he could obtain a modicum of air support, and if he could maintain the mobility of an armored division already on Luzon.
The three infantry divisions reached Luzon, but two lost fully a third of their troops and equipment to Allied air or submarine action on the way; one RCT of the third division had to be left on Formosa for lack of shipping. Worse still, scheduled shipments of supplies and equipment never arrived, and stocks available on Luzon were inadequate for the forces already there. No air reinforcements, Yamashita learned by mid-December, would be forthcoming. The Allies would be able to dominate the skies over Luzon and render the armored division immobile.
By mid-December Yamashita had concluded that the only course open to him was a static defense. He intended to delay the conquest of Luzon as long as possible in order to pin down as many U.S. divisions as he could in the hope of slowing Allied advances toward Japan. He prepared to undertake his task with understrength, underfed, and under-equipped ground combat forces, the leadership and organization of which left much to be desired.6
Logistically, Yamashita faced the proverbial insoluble problems and insurmountable obstacles.7 First, supplies on
Luzon were insufficient to provide properly for the 14th Area Army, and at the end of December General Muto, Yamashita's chief of staff, reported that "supply shortages had reached unexpected proportions."8 Second, the Japanese transportation system was completely inadequate for the task at hand--moving supplies from depots to defensive positions. Third, the system of supply control and distribution was chaotic until late December.
Chief shortages were ammunition, demolitions, construction equipment of all sorts, medical supplies, communications equipment and food. In brief, the 14 Area Army was ill equipped for a long campaign. The food situation alone would soon bring that fact home sharply. Even before the end of 1944 food stocks in the Philippines had been inadequate to satisfy both Japanese and Filipino requirements. Rice had to be imported from Thailand and French Indochina, and much of the rice harvested on Luzon had been sent to Leyte. With increased Allied air and submarine activity in the South China Sea, imports were drastically reduced until, in December, not a single shipload of food reached Luzon. As early as mid-November the food shortage on Luzon had reached such proportions that the 14th Area Army had cut its ration from a daily three pounds to about nine-tenths of a pound. Before mid-January men in some units would be lucky to get as much as a half a pound a day.
Many of Yamashita's supply problems stemmed directly from his transportation problems, for he found it impossible to move the supplies and equipment that were available, a condition resulting from many causes. For one thing, a Japanese infantry division had only 500 organic vehicles--as compared with the 2,125 in a U.S. Army division9--and none of the Japanese units on Luzon had its authorized number of vehicles. This shortage was compounded by a lack of fuel and lubricants. Moreover, the railroads on Luzon, never adequate for the scale of military operations envisaged by the Allies and Japanese, had been allowed to fall into "a shocking state of disrepair" during the Japanese occupation.10
Allied land-based and carrier-based air attacks, combined with guerrilla sabotage operations, multiplied transportation problems a hundredfold. Bridges were destroyed, highways cratered, railroad beds and marshaling yards damaged, railroad rolling stock and engines knocked out, and trucks destroyed. By 9 January the highways and railroads on Luzon, once the finest transportation network in the Pacific and Far East outside Japan, were in such condition that the 14th Area Army could move only a trickle of essential supplies to defensive positions.
Manila had long been the main supply depot for Japanese forces in the Philippines, the New Guinea area, and the Indies, and in June 1944 had also become the principal distribution and transshipment point for Southern Army supplies moving to Indochina and Malaya. As the main port of entry in the Philippines and the hub of Luzon's railroad
and highway network, Manila had also been the 14th Area Army's main supply point. Japanese naval forces operating in the Philippines and at points south had likewise stockpiled supplies and equipment there.
No centralized logistical authority existed at Manila, and many of the supplies did not come under Yamashita's control until after 1 January 1945. As a depot, Manila must have presented a chaotic picture, so much so that General Muto, remembering the mess after the war, was prompted to state that the supplies and equipment there "were piled in an unsystematic . . . helter-skelter way" and that there was "a lack of articles . . . required in the Philippines accompanied by plenty . . . for which there was no use."11
Yamashita had no intention of defending Manila. The efficacy of his defense of Luzon would therefore depend in large measure on how much of the 65,000 to 70,000 metric tons of Army supplies stockpiled there he could move out of the city to defensive positions elsewhere before the Americans arrived. Early in December he had found to his dismay that with existing transportation it would take six months to move the entire stockpile. But he had to do what he could, and issued orders to remove approximately 13,000 metric tons of the most vital supplies to northern Luzon by mid-January. Because of the transportation problem and Yamashita's lack of control over many commanders and units at Manila, only a little over 4,000 metric tons of the Manila stockpiles had been redisposed to northern Luzon by 9 January.
Command and Organization
As if his logistic problems were not enough, Yamashita's gods had also presented him with equally serious problems of command, organization, administration, and morale.12 Manila, for example, had long been cluttered with various headquarters, over many of which Yamashita had no control. Indeed, until mid-November at least, less than half the troops on Luzon were under Yamashita's command.13
The senior headquarters in Manila until 17 November was that of Terauchi's Southern Army. Directly under it, and all on the same level of command, were Yamashita's 14th Area Army; the 4th Air Army under Lt. Gen. Kyoji Tominaga; and a logistical headquarters, the 3d Maritime Transport Command, under Maj. Gen. Masazumi Inada. Also in Manila were three important naval headquarters. The first two were the Southwest Area Fleet and its subordinate echelon, the 3d Southern Expeditionary Fleet, both commanded by Vice Adm. Denshichi Okochi, who controlled all Japanese naval forces in the Philippines and who was responsible only to naval headquarters in Tokyo. The third naval headquarters was the 31st Naval Special Base Force under Rear Adm. Sanji Iwabuchi, who reported to Okochi.
In addition about 30,000 Army replacements, who had been stranded on Luzon for lack of shipping, were stationed
at Manila. The city had also become a collection point for Army and Navy men discharged from hospitals or rescued from vessels sunk in nearby waters. Control over the heterogeneous collection was divided among Southern Army, Southwest Area Fleet, and Imperial General Headquarters.
After mid-November steps were taken to bring order into this confusion of commands. Headquarters, Southern Army, moved to Saigon on 17 November, taking with it Inada's 3d Maritime Transport Command headquarters.14 Early in December Army replacements and convalescents passed to Yamashita's control, and the 4th Air Army was placed under him on 1 January. On the 6th Yamashita gained operational control of shore-based naval troops, but it was not until mid-January that the service troops of the 3d Maritime Transport Command passed to his command.15
His late assumption of control created many problems for Yamashita, whose opinion was:
The source of command and co-ordination within a command lies in trusting your subordinate commanders. Under the circumstances, I was forced [to defend Luzon] with subordinates whom I did not know and with whose character and ability I was unfamiliar.16
For example, Yamashita had trouble with General Tominaga and the 4th Air Army from the first. Before the air unit passed to Yamashita's control, Tominaga had provided no help in preparing defenses outside Manila. Instead, Tominaga worked on readying defenses of the city and environs, for he felt that the defense of Luzon would be meaningless if Manila were abandoned without a fight. It was not until he passed to Yamashita's control that Tominaga moved his headquarters and thousands of his troops out of the city.
The bulk of the units Yamashita commanded on Luzon could by no means be fitted into the category of first-class combat organizations. Divisions recently formed from former garrison units were badly organized, ill equipped, poorly officered, and miserably trained. In even worse state were the multitude of provisional infantry and artillery units that the Japanese organized on Luzon from the Manila replacements, ship survivors, convalescents, and, in some cases, Japanese civilians stranded in the Philippines. Even the regular units were in poor shape, many having suffered morale-shattering losses of men and equipment on their way to Luzon. The 23d Division, for instance, had lost its chief of staff, most of the other officers of division headquarters, and fully a third of its men. The 10th Division had suffered similarly, while only two-thirds of the 19th Division reached Luzon from Formosa before the Allied invasion put an end to further shipments.
Yet Yamashita had a respectable force, and one that was far stronger than General Willoughby, MacArthur's intelligence chief, had estimated. Instead of the 152,500 troops of Willoughby's estimate,
Yamashita actually had nearly 275,000 men.17 Willoughby, of course, could not know exactly what Yamashita planned to do with these troops; he did not anticipate an essentially static defense.
The General Defense Plan
Yamashita knew that within the framework of his plan for a protracted delaying action on Luzon he had no hope of defending all the island.18 He had neither the troops nor the equipment to do so, and the terrain in many places would not provide him with desired natural defensive positions or access to significant food-producing areas. Thus, he felt he could not defend the vital Central Plains-Manila Bay region against the superiority he knew MacArthur could and would bring to bear. Yamashita, therefore, did not intend to copy MacArthur's example of 1941-42 and withdraw into Bataan, which the 14th Area Army commander considered a cul-de-sac. On that relatively small peninsula, scarcely twenty by thirty miles in area, Yamashita's 275,000 troops could not hope to find food, and, concentrated in such a limited area, would quickly be cut to pieces by the superior air, naval, and artillery fire power available to MacArthur. By the same token, Yamashita had decided to leave undefended the southern shores of Lingayen Gulf, for he had concluded that the terrain there would make futile any attempt to hold that ground.
Having decided to abandon the Central Plains-Manila Bay region, Yamashita concentrated his forces in three mountainous strongholds that, he felt, the Allies could overrun only at the cost of many lives and much time. Only minor delaying actions, by isolated garrisons, would be undertaken at other points on Luzon.
The strongest and most important of the defense sectors covered all Luzon northeast and east of Lingayen Gulf. (Map 3) Included within this sector was the mountainous region east and northeast of the gulf as well as the fertile Cagayan Valley, ranking only second to the Central Plains as a food-producing area of the Philippines. To defend this northern stronghold Yamashita formed the Shobu Group, a force he retained under his direct command. Headquarters of the Shobu Group--identical with Headquarters, 14th Area Army--was located at Baguio, the cool and beautiful Philippine summer resort city, which lay about 5,000 feet up in the mountains and about twenty-five miles northeast of San Fabian on Lingayen Gulf.19
The Shobu Group numbered around 152,000 troops. Its major units were four infantry divisions (the 10th, 19th, 23d,
The Enemy on Luzon
11 January 1945
and 103d), the 2d Tank Division (less most of the 2d Mobile Infantry and other elements), and the 58th Independent Mixed Brigade (about half the size of a Japanese infantry division).20 The rest of the group included various 4th Air Army units, miscellaneous small combat and service organizations, and many provisional units of all types. The Shobu Group's principal missions were to prevent an Allied landing on the west coast of Luzon north of Lingayen Gulf, threaten the left flank of Sixth Army forces moving south through the Central Plains, deny the Americans access to the Cagayan Valley from the south, and, finally, conduct a protracted defense of the rugged, mountainous terrain it held.
The second defensive groupment Yamashita located in mountain country on the west side of the Central Plains overlooking the Clark Field area. This force, designated Kembu Group, was to deny to the Allies the use of the Clark Field air center as long as possible, threaten the right flank of Allied units moving down the Central Plains, and, when forced back from Clark Field, execute delaying operations in the Zambales Mountains, to the west of the air base.
Until late December the Kembu area was under the command of Lt. Gen. Yoshiharu Iwanaka, 2d Tank Division commander, who supervised the efforts of naval troops and part of his division to make defensive preparations. When on 1 January 4th Air Army passed to Yamashita's control, he ordered General Tominaga to set troops to work in the Kembu region, but left the group temporarily under Iwanaka's command, having some idea of moving the entire 2d Tank Division to the Clark Field area. The Allies reached Luzon before the 2d Tank Division could concentrate in the Kembu area, and Yamashita then placed the group under the command of Maj. Gen. Rikichi Tsukada, who also commanded the 1st Raiding Group, an airborne infantry unit previously controlled by 4th Air Army. Tominaga's 4th Air Army headquarters moved during the first week of January from Manila to Echague, in the north-central part of the Cagayan Valley.
Of the 30,000 men of Kembu Group, about half were naval airfield engineers, ground crews, antiaircraft units, and some ground combat organizations, all under Rear Adm. Ushie Sugimoto, the commander of the planeless 26th Air Flotilla. In addition to these troops and Tsukada's 1st Raiding Group, Kembu Group contained the 2d Mobile Infantry (less one battalion), a tank company, and other detachments from the 2d Tank Division; some field and antiaircraft artillery organizations; and a heterogeneous collection of service units from 4th Air Army.
The third major Japanese force was the Shimbu Group, under Lt. Gen. Shizuo Yokoyama, who also commanded the 8th Division.21 While responsible
for defending all southern Luzon, General Yokoyama was to concentrate his main strength in the mountains east and northeast of Manila. Yamashita ordered him not to defend the capital, but to keep troops there only long enough to cover the evacuation of supplies and delay the Allies by destroying important bridges. In the mountains east of the city, Yokoyama would control the dams and reservoirs that supplied Manila's water. His 80,000 men included the 8th Division (less the 5th Infantry, on Leyte), the 105th Division, various Army service and minor combat units, and some 20,000 naval troops under Admiral Iwabuchi of the 31st Naval Special Base Force.
In southwestern Luzon, Yokoyama stationed a reinforced infantry regiment from the 8th Division. A naval guard unit and miscellaneous 4th Air Army service organizations armed as auxiliary infantry held the Bicol Peninsula of southeastern Luzon, which was also in Yokoyama's sector. Many Japanese Army suicide boat units, whose members were ultimately to fight as infantry under Shimbu Group control, were stationed at various points along Luzon's southwestern and southern coasts.22
Dispositions in Northern Luzon
The Shobu Group
The first Japanese to establish contact with the Sixth Army were members of the Shobu Group.23 In late December 1944 that group had been disposing itself in what Yamashita intended to make his principal forward defenses in northern Luzon. The final defensive area, into which the Shobu Group would ultimately withdraw, formed a near-isosceles triangle in high, rugged mountains of that section of northern Luzon lying west of the Cagayan Valley. The southwestern anchor of the triangle was Baguio, whence the base line ran almost due east thirty-five miles to Bambang, located on Route 5 north of the exits of the mountain passes leading from the Cagayan Valley to the northeastern corner of the Central Plains. The apex of the triangle was Bontoc, at the junction of Routes 4 and 11 some fifty miles northeast of Baguio.
A basic tenet of Yamashita's plan for the defense of northern Luzon was to hold the approaches to the Cagayan Valley until that region could be stripped of foodstuffs and military supplies for the triangular redoubt. Yamashita expected that once the Sixth Army had secured the Central Plains-Manila Bay area it would strike his defensive triangle from the south, possibly making its main effort an attack into the Cagayan Valley via the Bambang approach. Yamashita had to hold the southern approaches to the triangle to keep open his supply lines from Manila and to maintain his line of communications to the Shimbu Group,
much of which he might transfer to the Shobu Group sector if time permitted.
The focal point for the defense of the southern approaches to the Cagayan Valley was San Jose, forty-five miles southeast of San Fabian and nearly the same distance south of Bambang. Situated at the end of one branch of the Manila Railroad, San Jose was also the site of the junction of Routes 5, 8, and 96. Route 5 led north to Bambang through Balete Pass and south from San Jose toward Manila along the eastern side of the Central Plains. Route 8 led northwest from San Jose toward Lingayen Gulf. Route 96 went southeast toward the east coast of Luzon.
San Jose was the main transshipment point for supplies going north from Manila or being moved out of Central Plains depots to the Shobu Group. Some supplies from December sailings to west coast ports such as San Fernando, La Union, were also reassembled at San Jose. During late December an average of 600 metric tons of all types of supplies and equipment, including most of the matériel from Manila, came into San Jose each day, much of it by rail. There, supplies were transferred to trucks or hand-carrying parties for further movement north along Route 5. So long as Yamashita could hold San Jose and control Route 5, he could continue to ship supplies north into the Shobu defensive triangle. Without San Jose, the group would be cut off from its principal sources of military supplies and equipment, and would have to rely on food and other supplies it could move out of the Cagayan Valley. Baguio became Shobu Group's most important secondary supply point. Yamashita planned to assemble there the many tons of supplies stockpiled at various west coast points during November and December.
From the first Yamashita realized that a glaring weakness in all his plans for the defense of northern Luzon was the absence of a good overland link between Baguio and Bambang. He urgently needed a road between the two towns not only to move troops rapidly between the two fronts but also to transport supplies to Baguio from the Cagayan Valley and from the stockpiles being established along Route 5 north of San Jose. Accordingly, Yamashita began construction late in December or early in January. The supply road swung east off Route 11 at a point about ten miles northeast of Baguio, and followed a narrow prewar mining and logging road--until then suitable only for light traffic--for the first ten or fifteen miles eastward. Then it swung east-southeast through the Caraballo Range, following a graded horse trail that American forces had constructed before the war, to Route 5 at Aritao, ten miles south of Bambang. By early February, the Shobu Group, using hand-carrying parties along much of the route, was able to move about a ton of supplies west along the improved road each day. It was mid-April before the whole road was open to trucks.
While Yamashita deployed a considerable portion of his strength in positions to defend the approaches to San Jose and the Bambang anchor of the defensive triangle, he did not neglect the other approaches to the triangular redoubt and the Cagayan Valley. He assigned responsibility for holding the Cagayan Valley and the north and northwestern coasts of Luzon to the 103d Division, to which he attached an understrength regiment of the 10th Division.
The 23d Division, with the 58th Independent Mixed Brigade (IMB) attached, held the west coast from Alacan north sixty-five miles, and was also responsible for defending the approaches to Baguio from the south and west.24 The 58th IMB had some troops as far north as San Fernando, but its main strength was concentrated along the coastal hills from Alacan north twenty miles to Aringay. Yamashita intended to deploy the 23d Division along an arc of high ground defenses running generally southeast from Alacan across Hill 200 and on another ten miles to the Cabaruan Hills, which controlled the Route 3 crossing over the Agno River. If they could not hold their assigned sectors, the 23d Division and the 58th IMB would fall back on Baguio, delaying along successive defensive lines.
The 23d Division had stationed an infantry battalion along the southwestern shore of Lingayen Gulf and had directed the battalion to delay an American drive down the west side of the Central Plains. A reconnaissance unit from the same division, with orders to withdraw without offering any resistance, was deployed along the gulf's southern shores, but had sped southward after the infantry battalion when ships of the Allied Naval Forces had begun preassault bombardment. It had been principally stragglers from these two 23d Division organizations that the XIV Corps and the 6th Division of I Corps had encountered on 9, 10, and 11 January.
In early January, the 10th Division, less the bulk of two infantry regiments, was responsible for the defense of San Jose. One regiment, less a battalion, was in the Bambang area attached to the 103d Division, and another, also minus a battalion, was far to the southwest on Bataan Peninsula. The division was, however, reinforced by the Tsuda Detachment, an understrength regimental combat team of the 26th Division.25 Stationed at Dingalen and Baler Bays on Luzon's east coast, Tsuda Detachment was to make a fighting withdrawal to the Central Plains in the event of an American landing on the east coast. Ultimately, both the 10th Division and the Tsuda Detachment would defend Route 5 through Balete Pass and secure the Bambang anchor of Yamashita's final defense triangle.
When the Sixth Army landed at Lingayen Gulf the 19th Division was at Naguilian, on Route 9 between Baguio and the west coast town of Bauang, seven miles south of San Fernando.26 Yamashita planned to move the 19th Division to a reserve position at San Leon, on Route 8 twenty miles northwest of San Jose. The 2d Tank Division (less most of its 2d Mobile Infantry) was in the southern part of the Central Plains, strung out along Route 5 south of San Jose.27 It was to defend against American
parachute landings in the Central Plains, hold itself mobile for a possible counterattack, prepare to withdraw up Route 5 into the Cagayan Valley, and be ready to move west across the Central Plains to the Kembu area.
The Effect of the Invasion
When on 6 January Allied Naval Forces' vessels started bombarding San Fernando and environs, Yamashita began to fear an imminent assault at the port city. Such an invasion, coming north of the 58th IMB's concentration, would endanger the security of Route 9 to Baguio, especially if the 19th Division were to deploy southward as planned. Quickly, Yamashita changed his plans for the 19th Division and directed the division commander, Lt. Gen. Yoshiharu Ozaki, to hold the coastal sector from Bauang north forty miles--an area previously assigned to the 58th IMB--and to maintain considerable strength at Naguilian to defend Route 9. The change in plans was not drastic. As a result of Allied air attacks and guerrilla operations, and because of the prevailing opinion within 14th Area Army that no American landings would occur before mid-January, the 19th Division had hardly started redeploying toward San Leon when its new orders arrived. The division had only to stay where it was to execute Yamashita's directive.
But the change upset Yamashita's plans for strengthening Shobu Group's southern flank and the approaches to San Jose and Bambang. He accordingly decided to organize four defense lines in front of San Jose and Bambang, employing the 2d Tank Division in a new role. The first line, the 23d Division's Alacan-Cabaruan Hills arc, presumably already in existence, would now be considered an outpost line of resistance behind which three new lines would be established. Yamashita decided that to gain time for the construction of the three new lines, he would have to strengthen the outer arc. Therefore he ordered the 2d Tank Division's Shigemi Detachment, roughly comparable to a combat command of an American armored division, to move from its concentration point on Route 5 south of San Jose and take station at the road junction town of Urdaneta, on Route 3 north of the Cabaruan Hills.28 Part of the detachment was to move on to reinforce 23d Division outposts at Binalonan, five miles north along Route 3 from Urdaneta.
Since many of the bridges along the main roads to Urdaneta had been destroyed, and since guerrilla and Allied air operations impeded movement over these roads, the Shigemi Detachment had to displace by night marches over secondary roads, approaching Urdaneta and Binalonan from the northeast. Dawn on 9 January found the detachment at San Manuel, five miles east of Binalonan.
Having decided that the road and bridge destruction would make it impossible for the 2d Tank Division to move across the Central Plains to the Kembu area, Yamashita now planned to move the rest of the division northeast behind
the Shigemi Detachment.29 The division (less the Shigemi Detachment and the 2d Mobile Infantry) would concentrate on the Agno near Tayug, six miles southeast of San Manuel. Here, the armored unit was to make ready to counterattack or, conversely, to defend a mean track known as the Villa Verde Trail, which wound north and east over rough mountains from the vicinity of Tayug to join Route 5 north of Balete Pass.
During the first days following Sixth Army's landings, many Shobu Group staff officers, dismayed by the American progress inland as well as by the increasingly adverse effect of Allied air and guerrilla operations on Shobu Group supply movements, implored Yamashita to mount an all-out counterattack, employing the 2d Tank Division as a spearhead. Such an attack, Yamashita's subordinates suggested, would gain valuable time to move supplies into the triangular redoubt. Even if only temporarily successful, the attack might provide Shobu Group with an opportunity to capture American supplies and move them into the mountains. But Yamashita concluded that Sixth Army was deploying great strength so slowly and cautiously that no situation favorable for a Japanese counterattack could arise in the near future. Furthermore, other staff officers advised him that the 2d Tank Division's fuel situation, combined with the condition of roads and bridges in the Central Plains, would make it impossible for the division to mount a cohesive counterattack. Yamashita felt that the only result would be the quick decimation of his armored strength and, envisaging an essentially defensive role for the entire Shobu Group, refused to risk any important elements of the group in a counterattack.
As one consequence of this decision, Yamashita committed the 2d Tank Division, still minus the Shigemi Detachment and most of the 2d Mobile Infantry, to the first of the three new defense lines in front of San Jose and Bambang. On 11 January he directed the division to concentrate at Lupao, on Route 8 nine miles northwest of San Jose, and to extend its left southeast to Muñoz, on Route 5 south of San Jose. Here, the division could better plug a gap between 10th and 23d Divisions' existing lines than would be possible if the unit were to move to Tayug, as Yamashita had directed only two days earlier. Moreover, the new deployment would bring strong defensive forces closer to San Jose and thus help forestall envelopment of that town from the west or south.
The responsibility for holding the second of the three new lines Yamashita assigned to the 10th Division which, with the arrival of the 2d Tank Division from the south, could redeploy some of its strength away from San Jose. On the northwest the second line was virtually an extension of the first, and stretched from Lupao to Tayug and the entrance to the Villa Verde Trail. The southeastern section of the second line stretched from San Jose southeast twenty-five miles to Bongabon, junction of the roads to Baler and Dingalen Bays on the east coast. The Tsuda Detachment, now directed to withdraw inland from the bays, would defend this section of the
second line to help prevent the outflanking of San Jose from the south and southeast.
Yamashita realized that his forces would be unable to hold out indefinitely in the relatively flat, open land in front of San Jose and that, accordingly, he would require a line in better defensive terrain along the approaches to the Bambang anchor of his triangle. Thus, the third new line of defenses he established in early January lay across Route 5 in the mountains some twenty miles north of San Jose and about seven miles south of Balete Pass. Responsibility for holding this third line was initially vested in the 10th Division, but Yamashita knew that, with the missions he had already assigned it, the unit would not have enough strength to defend the line. Therefore, on 8 January, he directed the 105th Division of Shimbu Group to start north from its positions east of Manila to deploy along the new Route 5 defensive line. The division's first echelon was composed of division headquarters, five infantry battalions, and an understrength artillery battalion. Indications are that Yamashita expected to have plenty of time to move the rest of the 105th Division northward, and that he may also have planned to bring north much of the 8th Division, leaving Shimbu Group only provisional Army units and the naval forces.30
As of 11 January the 105th Division's advance elements had barely started their trek northward. The 2d Tank Division's Shigemi Detachment was at San Manuel and had passed to the control of the 23d Division. Another combat command of the 2d Tank Division, the Ida Detachment, was still strung out along Route 5 twenty-five to thirty miles south of San Jose. The rest of the division, which was composed of division headquarters, division troops, the 10th Tank Regiment, and a battalion each from the 2d Mobile Infantry and the 2d Mobile Artillery Regiments, was moving into position along Route 8 northwest of San Jose.31
On 11 January the 23d Division and the 58th IMB held excellent defensive positions in the area east and north of Alacan on Lingayen Gulf, but the 23d Division's outer arc of defenses from Alacan to the Cabaruan Hills was weakly garrisoned. On its own initiative the division had decided that the Alacan-Cabaruan line would prove indefensible if American forces landed substantial strength over Lingayen Gulf's southern shores and swung thence generally southeastward. Therefore, the division had prepared its principal defenses in higher
terrain east of the Alacan-Cabaruan line, disposing most of its strength in rising ground east of Route 3 from Sison, about seven miles inland from Alacan, south and southeast ten miles to Binalonan and San Manuel.
General Muto, Yamashita's chief of staff, had discovered this unauthorized redeployment during an inspection tour on 5 January. Muto agreed that the 23d Division could not hold back a concerted American drive southeast from Lingayen Gulf, but he was alarmed at the prospect that the Sixth Army, encountering no substantial defenses in the region west of Route 3, would be able to initiate a drive toward San Jose far sooner than anticipated, thereby upsetting all Yamashita's plans. Muto therefore directed the 23d Division to reinforce its Alacan-Cabaruan Hills line forthwith. Obviously in no hurry to comply with these orders, the 23d Division, by 11 January, had sent forward from its Sison-Binalonan-San Manuel positions only one infantry company and half a battery of artillery. As the division would soon learn, further opportunities to strengthen the Alacan-Cabaruan Hills arc had passed.
1. The general sources for most of this chapter are: Japanese Operations in the Southwest Pacific Area (vol. II of the 3-volume SWPA Hist Series, prepared by G-2 GHQ FEC) (hereinafter cited as SWPA Hist Series, II), pp. 281-86, 295-302, 310-11, 337-43, 404-37; Japanese Studies in WW II, No. 5, 4th Air Army Opns, 1944-45, pp. 64-77; No. 6, 14th Area Army Plans, 1944, pp. 12-25, 28-37, 44-45; No. 8, 14th Area Army Operations on Luzon, pp. 2-3, 6-40; No. 11, 35th Army Operations, 1944-45, pp. 23-34, 114, 119, 127; No. 21, History of Southern Army, pp. 61-70, 73-80, 83-84; No. 72, History of Army Section Imperial GHQ, pp. 123-27, 131-48, 153-61; Memoirs of Lt Gen Akira Muto (CofS 14th Area Army), in G-2 GHQ FEC, Translations of Japanese Documents (4 vols., hereinafter cited as Trans, copies in OCMH files), II, Item 20 (hereinafter cited as Muto Memoirs), pp. 7-17, 22-24, 31.
2. In addition to the sources cited in note 1, this section is based on: United States Strategic Bombing Survey (Pacific), Naval Analysis Division, Interrogations of Japanese Officials (2 vols., Washington, 1946), II, 500-30, Interrog of Vice Adm Shigeru Fukudome (Comdr 2d Air Fleet); Interrog of Gen Yosbijiro Umezu (CofS Japanese Army), USSBS (Pacific), Interrog No. 488, copy in OCMH files; Maj Gen Yoshiharu Tomochika (CofS 35th Army), The True Facts of the Leyte Operation, passim, originally published in Japan in 1946, translated MS copy in OCMH files; Statements of Maj Gen Toshio Nishimura (an ACofS 14th Area Army), States, II, 677, 687; Statement of Lt Gen Jo Iimura (CofS Southern Army), States, I, 540-41; Rpt of Joint Research by Gen Iimura, Lt Gen Shuichi Miyazaki (Chief Opns Dept Army Sec Imperial GHQ), Col Takushiro Hattori, Col Kazutsugu Sugita (both on Miyazaki's staff), States, II, 498-502; Before the Military Commission Convened by the United States Army Forces Western Pacific, United States of America versus Tomoyuki Yamashita, Public Trial (hereinafter cited as USA vs. Yamashita), pp. 3623-3665 (Yamashita testimony), p. 3007 (Muto testimony).
3. See Cannon, Leyte.
4. For subsequent operations of the 35th Army, see below, chs. XXX-XXXII.
5. Iimura returned to Saigon on 24 December and Miyazaki to Tokyo on the 25th. Apparently, Iimura's original mission had been to see to it that Yamashita followed Terauchi's instructions to the letter. If so, the mission must have been considered a failure by Terauchi. Perhaps only coincidentally, Iimura immediately found himself with a new assignment--on 26 December he was given command of the almost defunct 2d Area Army in the Indies.
6. Japanese Studies in WW II, No, 6, 14th Area Army Plans, pp. 33-34, 50; No. 8, 14th Area Army Opns on Luzon, pp. 2-3, 24; Statement of General Tomoyuki Yamashita, States, IV, 500; Muto Memoirs, pp. 12-13; Nishimura Statement, States, II, 677-78; Shobu Gp (14 Area Army) Opns Dept, Outline of Operational Policy for Luzon, 19 Dec 44, and apps. I and II thereto, 20 Dec 44, Trans, III, pt. I, pp. 16-28. Colonel Volckmann, guerrilla leader in northern Luzon, believed on the basis of documents his men had captured from the Japanese that Yamashita had reached his decision for a static defense before the end of November. The November plans had called for operations primarily defensive in character, hedged by "if" provisions for a counterattack. The December plans left out even the "if" provisions for a counterattack.
7. Additional sources used for this subsection include: Japanese Studies in WW II, No. 9, Luzon Operations of the Shimbu Group, pp. 4-5; No. 10, Operations of the Kembu Group, pp. 2, 5-6; Nishimura Statements, in States, 690-94; USA vs. Yamashita, pp. 2999, 3014, 3027-28 (Muto); ibid., pp. 3540, 3566 (Yamashita); ibid., pp. 3013-14, 3219 (Lt Col Kikuo Ishikawa, Supply and TO 14th Area Army); ibid., p. 3190 (Maj Gen Goichi Kira, Intendance Off, 14th Area Army); 10th Info and Hist Serv Hq Eighth Army, Staff Study of Japanese Operations on Luzon, Narrative of Col Ryoichiro Aoshima (Chief LofC Sec, 14th Area Army), pp. 5-8, 12-13; 10th I&H Staff Study, Japanese Opns on Luzon, Narrative of Col Shujiro Kohayashi (Opns Off 14th Area Army and Shimbu Gp), pp. 1-2; ibid., Narrative of Col Yasuji Okada (CofS Kembu Gp), p. 16; ibid., Narrative of Col Shigeo Kawai (Staff 2d Tank Div), pp. 4-5; ibid., Aoshima Interrog, p. 7.
8. Muto Memoirs, p. 13.
9. TM-E 30-480, Handbook on Japanese Military Forces, p. 23; FM 101-10, Staff Officers Field Manual: Organization, Technical, and Logistical Data, 1945, par. 121.
10. Muto Memoirs, p. 13.
11. USA vs. Yamashita, p. 2999 (Muto testimony).
12. Additional sources used in the preparation of this subsection are: USA vs. Yamashita, pp. 3524-26, 3655 (Yamashita); ibid., pp. 3001-02, 3008-09 (Muto); ibid., pp. 2533-36 (testimony of Vice Adm Denhichi Okoochi, more commonly Denshichi Okochi, Comdr Southwest Area Fleet); ibid., Defense Exhibit J, Org Chart prepared by Muto.
13. See app. C-1.
14. By this time Inada was an "evacuation expert." He had arrived in western New Guinea in late 1943 to assume command of a supply organization there; went to Hollandia to take command of the 6th Air Division in April 1944; made his way westward overland to the Wakde-Sarmi area after the Allied invasion of Hollandia, arriving shortly after the Allied landings near Sarmi on 17 May; again escaping, went to the Philippines; moved to Saigon in November; and wound up to survive the war as a ground commander in Japan proper.
15. See app. C-2.
16. USA vs. Yamashita, p. 3655 (Yamashita).
17. General Willoughby did not change his estimate of Japanese strength significantly until the campaign was nearly over.
18. In addition to relevant documents cited in note 1, this subsection is based on: 14th Area Army Opns Orders, Trans, III, pt. III, Item 3, pp. 8-18; Nishimura Statement, States, II, 691-92; Yamashita Statement, States, II, 497; Statement of Col Kenichiro Asano (CofS 8th Division and ACofS Shimbu Gp), States, I, 90-92; USA vs. Yamashita, pp. 2536-38 (Okochi testimony); ibid., pp. 3527-28 (Yamashita); Japanese Studies in WW II, No. 9, Luzon Opns of the Shimbu Gp, pp. 1-5; No. 10, Opns of the Kembu Gp, pp. 1-6; 14th Area Army Home Organization Board (a sort of veterans group), 14th Area Army Tr Org List (prepared in Japan, Dec 46), trans in OCMH files.
19. SHOBU was the code name for the 14th Area Army as well as the name of the northern defense group. In Japanese plans, orders, and reports, the distinction between the group and the army is sometimes elusive, but in this narrative the term Shobu Group is reserved for the northern defense sector.
20. The 61st IMB, stationed on the Batan and Babuyan Islands off northern Luzon, was nominally part of the Shobu Group but is not included in the foregoing totals. The unit remained unmolested on its islands until the end of the war, playing no part in the Luzon Campaign. Of the total of some 150,000 in the Shobu Group, about 140,000 were in uniform as of 9 January. The remainder consisted of civilian government and military employees, many of whom were drafted into the service before the campaign was over.
21. The staffs of Shimbu Group and 8th Division headquarters were somewhat different, although many officers served on both.
22. Further information on dispositions in southern Luzon is to be found in Chapters XII and XXIII, while material on the deployment of the main body of the Shimbu Group is set forth in Chapters XXI and XXII.
23. The general sources for this section are: SWPA Hist Series, II, Japanese Opns in the SWPA, 418-25, 430-37; Japanese Studies in WW II, No. 8, 14th Area Army Opns on Luzon (hereafter cited as 14th Area Army Opns on Luzon), 6-15, 26-28, 36-40; 10th I&H Staff Study, Japanese Opns on Luzon, Aoshima Narrative, pp. 3-4, 7-10, and atchd Maps Nos. 1 and 2; Statement of Maj Gen Haruo Konuma (Vice CofS 14th Area Army), States, II, 300-302, 305-09, 327-30; 14th Area Army Tr Org List.
24. Additional information on the 23d Division and the 58th IMB is from: Statements of Maj Gen Bunzo Sato (CG 58th IMB), States, II, 253-54, 259-62; Statement of Col Masaichi Takahashi (Staff 23d Div), States, IV, 42-43.
25. The Tsuda Detachment contained the 11th Independent Infantry Regiment (less 2d Battalion) of the 26th Division, a battery of medium artillery, and miscellaneous service troops, all under Col. Tsukada Tsuda. The rest of the 26th Division was on Leyte.
26. Additional information on the 19th Division comes from: Statement of Lt Gen Yoshiharu Ozaki (CG 19th Div), in States, III, 177; Nishimura Statement, States, II, 677-80.
27. Additional information on the 2d Tank Division is from Statement of Col Shigeo Kawai (Staff 2d Tank Div), States, II, 145-49.
28. The Shigemi Detachment was named after Maj. Gen. Isao Shigemi, also the commander of the 3d Tank Brigade, 2d Tank Division. It consisted of the 7th Tank Regiment, a battalion (less elements) of the 2d Mobile Infantry, and miscellaneous reinforcing elements. The 7th Tank Regiment had taken part in the Philippine Islands Campaign of 1941-42, but had apparently been completely reconstituted since then.
29. Actually, the destruction was great enough to forestall the division's move westward by about 25 December, while Yamashita did not cancel plans to move the unit to the Kembu area until 9 January. The delay in issuing the cancellation order probably provides a bleak commentary on the state of Japanese communications on Luzon.
30. At least initially, the redeployment of the 105th Division was apparently partially intended as a means of permitting the 2d Tank Division to move to the Kembu area. But plans to move the tank division west were canceled the day after Yamashita issued the movement orders to the 105th Division, without a concomitant cancellation of 105th Division orders. Therefore, it appears that Yamashita intended to move the 105th Division north to the Shobu area no matter where the 2d Tank Division was ultimately deployed. Hints that Yamashita planned to bring the 8th Division north are more elusive, although the move would have been logical in the context of his plan to make his principal stand in northern Luzon. A thesis that Yamashita may have intended to denude the Shimbu Group of its regular Army combat units is supported by the fact that just one tank regiment of the 2d Tank Division held defensive positions in the Shimbu area until the end of the first week of January.
31. The Ida Detachment was named after Col. Kumpei Ida, the commander of the 6th Tank Regiment, around which the detachment was built. The detachment had previously held defenses at Ipo Dam, in the Manila watershed area, under Shimbu Group control. The 10th Tank Regiment was commanded by Col. Kazuo Harada.