Area Map

US 6-AUS 6-IDThe Sixth Army (6-A) landed on the southeastern shores of Lingayen Gulf, Luzon Island, on January 9, 1945, against relatively light enemy opposition. A beachhead was established and all units continued to push the attack in a southerly direction through the central plains. On March 3, the city of Manila fell to elements of the XIV Corps. Through subsequent landings, the southern tip of Bataan and the Island of Corregidor were taken. The 6-A maintained the initiative with attacks toward the southern half of the island and toward the Sierra Madre Mountains to the east. The final mission assigned to the 6-A, to gain control of the entire island of Luzon, was well underway.

The 6th Infantry Division, less the 63rd Infantry Regiment, landed with the assault echelon of one Corps and participated in the drive for Manila by furnishing protection for the left flank of the 6-A. The 63-IR was initially in the Corps reserve. The Division destroyed enemy resistance encountered in the Cabaruan Hills; defeated elements of the Japanese 2nd Armored Division at Munoz; seized and secured the high ground south of San Jose; cut the island of Luzon in half by seizure of Baler Bay and Dingalan Bay on the east coast. During the period February 24, 1945 – April 19, 1945, the 6-ID was engaged in operations against the Shimbu Line, east of Manila.

Mortar Crew on the beach - Gulf of Lingayen

The General Situation

US XI CorpsUS XIV CorpsOn March 15, the XI Corps relieved the XIV Corps in operations against the Shimbu Line. At this time the VI Corps was composed of the 6th Infantry Division, the 43rd Infantry Division, and the 112-RCT (CAV). The 6-ID, in the center of the Corps zone, was ordered to attack the Montalban sector of the Shimbu Line. The division’s plan of attack was simple. The 1-IR and the 20-IR were used to spearhead the advance and attack on Mount Mataba and Mount Baytangan from the southeast, while the 63-IR protected the left flank of the Division. The Shimbu Line, located east of Manila in the Sierra Mountains, extended from Ipo Dam in the north to Antipolo in the south. The enemy had his forces generally concentrated in five sectors, Antipolo; Marikina; Central (Mount Baytangan); Montalban and Ipo Dam. An estimated 17.000 troops occupied the Shimbu Line. The Montalban Sector, located generally in the center, consisted of Mount Oro (1000 feet), Mount Pacawagan (1500 feet), and Mount Mataba (1400 feet). Mount Mataba dominated the Marikina River Valley.

American soldiers of the 33-ID and Filipino resistance fighters carry supplies along a trail during the fight to regain the Philippines. Baguio, Luzon, Philippines, April 1945, (Carl Mydans)

Its main ridge ran generally north and south with three prominent peaks, Knob 1 on the southern tip, Red Top in the center, and Knob 2 on the northern tip. The western approaches to Mount Mataba consisted of steep hogback ridges with deep ravines covered by a dense growth of vegetation and trees. Elements of the Japanese 8th and 105th Divisions, 26th Independent Mixed Brigade, and miscellaneous service units were located in this area. They had spent months preparing positions in this sector, consisting of an elaborate network of mutually supporting caves with connecting underground tunnels covering all avenues of approach leading to Mount Mataba.

The men of the 6-ID were considered in the category of seasoned troops. In addition to their operations in Luzon, they had experienced considerable combat in New Guinea. Replacements were quick to acquire the fighting spirit of the unit because of its high esprit de corps. Morale was excellent. At this time logistical support was adequate. On the other hand, the enemy had suffered reverses and was occupying defensive positions, nevertheless, his morale was assumed to be excellent. Captured documents indicated that his supplies were sufficient, in that he had placed a six months stockpile of supplies in this area. Taking everything into consideration the combat efficiency of the opposing forces was considered equal.

American soldiers of the 33-ID carry supplies along a trail during the fight to regain the Philippines, Baguio, Luzon, Philippines, April 1945, (Carl Mydans)

Disposition and Plans of the 63rd Infantry Regiment

From March 15 to April 5, the 63-IR protected the left flank of the Division extending from the vicinity of Ipo Dam in the north to San Mateo in the south. During the period of April 6-9, the 63-IR attacked Mount Mataba with two battalions, the 2/63 and 3/63, to seize objectives A, B, and X from the southwest but was repulsed with heavy losses. On April 10, the regiment planned to attack with all three battalions to seize objectives A, B, X, and 0. The 1/63 was to make a surprise attack from the west, under the concealment of darkness, to seize and hold objective G (Mount Mataba). The 2/63 was to seize objective X from the south while the 3/63 was directed to capture objectives A and B.

Disposition and Plans of 1/63-IR

The battalion planned to attack Mount Mataba from the west at 0400, April 10, with two companies abreast, Able and Charlie. Charlie on the right; would attack up Ridge R while A would attack up Ridge S. Baker Co, in reserve, would protect the routes of supply and evacuation. Each assault company was reinforced with one section of machine guns from Dog Co. The 81-MM mortars were to be placed in general support from positions west of San Mateo. For this operation, one platoon of tanks and one platoon of 4.2 mortars were attached to the battalion.

The Company Situation

George Co had occupied a portion of the battalion’s defensive position, southwest from Novaliches Water Shed, along the pipeline which supplied the water for Manila. Daily patrols had been dispatched to the east to reconnoiter the area around Ho Name Gorge and other ravines in the vicinity of Mount Mataba in an effort to determine routes of advance, enemy strength, and dispositions. These patrols reported that all ravines were thickly wooded and covered with a dense growth of underbrush providing excellent concealment for enemy installations. They further reported that the area was void of any trails except for a few narrow footpaths. It was known that the enemy had constructed an elaborate system of mutually supporting caves and foxholes, connected by underground tunnels. These positions were located on the commanding ground covering all approaches to Mount Mataba. These approaches crossed flat rice paddies in the Mariquina River Valley and were subject to constant hostile observation.

The strength of Charlie Co just prior to the jumpoff was 90 enlisted men and 2 officers, (the company commander and the 1st platoon leader) of this strength approximately one-fifth were replacements who had been received in the past month. They had been given as complete an orientation and indoctrination into combat as possible by being utilized to the fullest on combat and reconnaissance patrols and in setting up ambushes. The composition of all patrols was carefully supervised to ensure that each patrol had a proportionate share of combat veterans and was commanded by a reliable non-commissioned officer. While the company had been guarding the pipeline they received a well-earned rest, which, in conjunction with three hot meals daily, had raised morale to a new high. The combat efficiency of the company was considered to be excellent. Captured documents indicated that the enemy was determined to make the seizure of Mount Mataba a costly as well as a timely operation. The Japs were prepared to defend each position at all costs which might easily tend to dissipate the strength of the main attack to several separate individual operations in the reduction of these defensive positions. Throughout this period the weather was hot and humid with excellent visibility during the day. With the exception of a shower on April 14, the weather was clear.


Company Plan of Attack

The company planned to attack in a column of platoons, the men in a single file. The 1st Platoon, with Dog Co’s machine gun section attached, would lead the attack up the Razorback Ridge to seize and hold Mount Mataba. The forward command group was to follow behind this platoon. The 2nd Platoon, with the company’s light machine guns attached, would be in support. This platoon would furnish flank protection by fire and would follow behind – the forward command group. The remainder of the command group followed the 2nd Platoon. The 3rd Platoon, also in support, following the rear command group, was to protect the rear of the company and assist in the evacuation of casualties.

The artillery forward observer and his party were placed with the forward command group, while the 81-MM mortar observer accompanied the 1st Platoon. No 60-MM mortar observers were to be used from the mortar section, but would be employed to carry extra ammunition as a resupply problem was anticipated. Platoon leaders and key non-commissioned officers were to adjust their own 60-MM mortar fire. Communication would consist of SCR-526 radios within the company command net and one SCR-300 radio in the battalion command net. The company was instructed that the battalion communication officer would lay wire from the battalion to the company area of departure. At this point, the company would be responsible for continuing this line as the unit advanced. No line of departure was to be used but rather an area of departure. The platoon leaders were informed that trucks would be spotted in the vicinity of the rear assembly area at 2330, April 9, to move the company to the area of departure. The company would remain in the latter area only long enough to detruck, assume the designated formation, and move out. The attack was scheduled for 0400 on April 10, approximately one hour before daylight. The element of surprise was stressed; supporting fires were planned, but would not be delivered except on call of the company.

Snipers ready

Final Preparations and Movement

Since a minimum amount of time would be spent in the area of departure, platoon leaders were instructed that blankets and extra equipment would be stacked in platoon piles in the rear assembly area. One bandoleer of ammunition and two combat-type K rations were issued to each man. Squad leaders were ordered to make last-minute checks to ensure that each man had his poncho, extra pair of socks, and two full canteens of water. All men were briefed on the necessity of maintaining strict light discipline and keeping noise to a minimum. Coffee and hot sandwiches were served at 2300. The company departed from the rear assembly area at 0100, on April 10, and arrived at the area of departure at 0200. The men detrucked, formed quickly, and moved out promptly at 0215.

Island Map

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