The Battle of Bunker Hill was fought between 9 August and 30 September 1952 during the Korean War between United Nations Command (UN) and Chinese forces over several frontline outposts.
Background In March 1952 the US 1st Marine Division was transferred to US I Corps and moved onto the Jamestown Line, the UN's Main line of resistance (MLR) across Korea. The segment of the Jamestown Line assigned to the 1st Marine Division extended southwest from the Samichon River and the left flank of the British 1st Commonwealth Division, crossed the 38th Parallel (the original demarcation between North and South Korea) shifted to the south bank of the Imjin River in the vicinity of Munsan-ni, continued to the conflux of the Imjin and Han River, and then followed the south bank of the Han past the Kimpo Peninsula.
Opposing the Marines on the Jamestown Line, the Chinese People's Volunteer Army (PVA) had the 65th and 63rd Armies, totaling 49,800 troops.
Battle Outpost Siberia (9–10 August) Shortly after midnight on 9 August, the PVA seized Outpost Siberia (Hill 58A), the site of a squad-size outpost, and also probed the positions of the 1st Marine Regiment. Siberia lay midway between the MLR and the line of PVA outposts. PVA possession of Siberia would provide observation posts to adjust artillery and mortar fire against the nearest segment of the Jamestown Line. As a result, Colonel Walter F. Layer's 1st Marines, on the right of the division's line, counterattacked at once, using the same unit, Company E, 2nd Battalion, 1st Marines that had dispatched the squad driven from Siberia. PVA artillery and mortar fire, directed from Hills 110 and 120, stopped the counterattack short of its objective. The Marines called for air strikes and additional artillery fire before renewing the counterattack on Siberia. At 06:50, four F9F jets from the 1st Marine Air Wing struck, dropping Napalm and 500-pound bombs. Shortly before 10:00, Air Force F-80 jets dropped 1,000-pound bombs, and a platoon from Company A, 1st Battalion, 1st Marines, the regimental reserve of the 1st Marines, stormed the hill, with the support of a platoon from the 2nd Battalion's Company E. The PVA again replied with mortars and artillery but could not stop the assault, which seized the crest. The supporting platoon from Company E joined in organizing the defense of the recaptured outpost, which came under a deadly torrent of accurate fire that forced the Marines to seek the protection of the reverse slope, nearer the MLR, where they held out until midafternoon before falling back. The PVA's artillery and mortars had fired an estimated 5,000 rounds, wounding or killing three quarters of the Marines who had attacked Siberia on the morning of 9 August. While Companies E and A reorganized the task of recapturing Siberia fell to Company C, which attacked with two platoons starting uphill at 01:16 on 10 August. A firefight erupted, lasting four hours, but the Marines gained the crest and held it until dawn, when driven from Siberia by a PVA counterattack. The losses suffered by the 1st Marines, 17 killed and 243 wounded within 30 hours, convinced Colonel Layer that his regiment could not hold Siberia if Hill 122, nicknamed Bunker Hill, remained in PVA hands. He and his staff planned a sudden thrust at Bunker Hill, possession of which would enable his command to dominate Siberia and observe movement beyond the PVA outpost line.
Battle for Bunker Hill (11–15 August) To disguise the true objective, Lieutenant Colonel Roy J. Batterton attacked Siberia at dusk on 11 August with one company from his 2nd Battalion. The 1st Tank Battalion supported the maneuver with four M46 Patton tanks each mounting a 90mm gun and an 18-inch searchlight fitted with shutter to highlight a target in a brief burst of illumination, and four M4A3E8 tanks, each carrying a flamethrower. While the M46s hammered Hill 110, the M4A3E8s climbed Siberia, using bursts of flame to light their way and gained the crest before doubling back toward Marine lines. As the flame-throwing M4A3E8 withdrew, the M46s opened fire on both Siberia and Hill 110, illuminating targets with five-second bursts of light from their shuttered searchlights and Company D overran Siberia, holding the crest until midnight when the diversionary attack ended.
The Bunker Hill assault force, Company B, 1st Battalion, 1st Marines under the operational control of Batterton's 2nd Battalion—reached the crest by 22:30 and began driving the PVA from the slope nearest the MLR. The PVA defenders recovered from their initial surprise, but the bypassed pockets of PVA soldiers, though they tried to resist, could not check the Marine advance. In the wake of the assault force, other Marines and members of the Korean Service Corps manhandled sandbags, wire, and shovels up the hill to help Company B organize the defenses of the objective against the counterattack that was certain to come. PVA mortars and artillery harassed the Marines on Bunker Hill until dawn on 12 August, but the counterattack did not come until mid-afternoon, after Company B passed under the operational control of 3rd Battalion, 1st Marines. The defense of Bunker Hill became the responsibility of the battalion commander, Lieutenant Colonel Gerard T. Armitage. The volume and accuracy of the shelling increased at about 15:00, a barrage that lasted an hour and forced the Marines to seek the protection from direct fire afforded by the reverse slope. Company I, 3/1 Marines, reinforced the embattled Company B in time to help break up an attack by some 350 PVA and hold the southern slope of Bunker Hill.
While the battle raged on Bunker Hill, 1st Marine Division commander General John T. Selden moved his reserves closer to the fighting. Company I, 3rd Battalion, 7th Marines, took the place of Company I 3/1 Marines on the MLR, and by the end of the day, all of the 3/7 Marines, had come under the operational control of the 3/1 Marines. Selden attached the 2nd Battalion, 7th Marines, to strengthen the reserve of the 1st Marines. Meanwhile, Col. Layer moved two provisional platoons from his reserve, the 1st Battalion, to reinforce the 3rd Battalion, and the 3rd Battalion's reconnaissance platoon established an outpost on Hill 124, linking Bunker Hill with the MLR. This shuffling of units proved necessary because the 1st Marine Division was so thinly spread over an extended front. During the realignment, supporting weapons, ranging from machine guns through mortars and artillery to rocket batteries, prepared to box in the Marines holding the near slope of Bunker Hill, hammer the PVA at the crest and beyond, protect the flanks, and harass movement on the routes PVA reinforcements would have to use. As daylight faded into dusk on 12 August, the Marines defending the reverse slope of Bunker Hill struggled to improve their hurriedly prepared fortifications, for the anticipated PVA night counterattack. The comparatively gentle incline of the reverse slope of the ridge that culminated in Bunker Hill reduced the amount of dead space that could not be covered by grazing fire from the Marine position. Moreover, weapons on the Jamestown Line could fire directly onto the crest, when the expected attack began. By 20:00, all the supporting weapons had registered to help the two companies hold the position.
Just as the Marines had attacked Siberia on the evening of 11 August to divert attention from Bunker Hill, the PVA sought to conceal the timing of their inevitable counterthrust. Shortly before midnight on the night of 12 August, the PVA probed the division's sector at three points. While one PVA patrol was stumbling into an ambush set by Korean Marines, another harried a Marine outpost east of Bunker Hill. The third and strongest blow, however, landed after midnight at Stromboli, a Marine outpost on Hill 48A northeast of Bunker Hill at the far right of the sector held by the 1st Marine Regiment, near the boundary with the 5th Marine Regiment. In conjunction with the attack on Stromboli, launched in the early hours of August 13, the PVA hit Company F on the right of the line held by the 1st Marines. The PVA failed to crack the Jamestown defenses, but they inflicted so many casualties at Stromboli that reinforcements had to be sent. The reinforcing unit, a squad from Company F, came under mortar and machine gun fire from the PVA probing Company F's defenses and had to return to the MLR. Pressure against Stromboli and its defenders continued until the commander of Company F sent a stronger force that fought its way to the outpost, breaking the PVA encirclement. The 5th Marines moved one company into a blocking position behind the Jamestown Line near Stromboli in case the fighting again flared at that outpost.
Meanwhile, the PVA attempted to seize Bunker Hill. At about 01:00 on 13 August, intense PVA artillery and mortar fire persuaded Captain Connolly of Company I to request box-me-in fires, which the 11th Marine Regiment provided immediately. PVA infantry, supported by machine gun fire, advanced behind bursting shells, but the Marines fought back with every weapon they could bring to bear - artillery, mortars, tank guns, rockets, rifles, and automatic weapons. After almost four hours, the violence abated as the PVA relaxed his pressure on Bunker Hill. Company G, 3/7 Marines, joined 3/1 Marines before the PVA broke off the action and withdrew behind a screen of artillery and mortar fire. Except for a determined few, whom the Marines killed, the PVA abandoned Bunker Hill. Colonel Layer took advantage of the lull to send Company H, 3/7 Marines, to relieve the Marines holding the hill. He afterward withdrew all the other elements of the 7th Marines that had reinforced his regiment, but not until a patrol from Company I had reconnoitered the far slope of the hill.
In keeping with their usual tactics, the PVA tried to divert attention from Bunker Hill before attacking again. Mortars and artillery shelled Combat Outpost 2, overlooking the Panmunjom corridor on the left of the sector held by the 3/1 Marines, and also harassed the MLR nearby. The main PVA thrust, directed as expected against Bunker Hill, began at about 21:00 on the night of 13 August. While shells still exploded on Combat Outpost 2, the PVA intensified the bombardment of Bunker Hill, which had been under sporadic fire throughout the afternoon. PVA troops hit Company H, attacking simultaneously near the center of the position and on the right flank. High explosive shells boxed in the Marines, and illuminating rounds helped them isolate and kill the few PVA who had penetrated the position. The Chinese battalion that attacked Bunker Hill on the night of 13 August again tested the Marine defenses at 02:25 on 14 August. Before this unit's second attack, a PVA machine gun on Siberia began firing onto Bunker Hill. Marine M-46s illuminated Siberia with briefly with their searchlights and silenced the weapon with 90mm fire, revealing the position of the tanks and enabling PVA artillery fire to wound a crewman of one of them.