As thousands of soldiers from the Republic of Korea Army (ROK) began to withdraw through the valley, the PVA infiltrated the brigade position under the cover of darkness, and assaulted the 3 RAR on Hill 504 during the evening and into the following day.

The fighting helped blunt the PVA Spring Offensive and the actions of the 2 PPCLI and 3 RAR at Kapyong were critical in preventing a breakthrough against the UN central front, the encirclement of US forces in Korea, which were at that point in general retreat, and ultimately, the capture of Seoul.

The 2 PPCLI and 3 RAR battalions, consisting of about 700 men each, bore the brunt of the assault and stopped PVA divisional forces estimated at 20,000 in strength during the hard-fought defensive battle.

[6] Following the Battle of Maehwa-San, the 27th British Commonwealth Brigade[note 1] were assigned to a period in US IX Corps reserve as the UN forces had continued to push steadily northwards.

[20][22] Meanwhile, planning began for Operation Dauntless, a drive 30 km (19 mi) into the Iron Triangle—a key PVA/Korean People's Army (KPA) concentration area and communications junction in the central sector between Chorwon and Kumwha in the south and Pyonggang in the north.

[5] However, with the US Eighth Army not strong enough to prevent large penetrations along its line, masses of PVA infantry soon swept around its flanks, surrounding entire formations in an attempt to cut off their withdrawal.

The brigade's stand on the Imjin River held off two PVA divisions for two days and ultimately helped prevent the capture of Seoul, but resulted in heavy casualties in one of the bloodiest British engagements of the war.

[40] The 2 PPCLI subsequently occupied Hill 677 and began digging-in, deploying their six Vickers machine guns in sections to add depth, and using defensive fire tasks to cover the gaps in their positions.

[42] In response to US IX Corps' requirements, Burke directed Ferguson to site his headquarters in the low ground of the valley in the vicinity of the hamlet of Chuktun-ni, so as to control the withdrawing ROK.

An outpost on the northern knoll reported PVA massing on their flanks at 23:00, and although heavy artillery was directed against the attackers, the section was forced to break contact and withdraw to the main defensive position.

[66][67] By dawn, it was clear that the PVA had succeeded in penetrating the perimeter through a gap between the 3 RAR platoons, and they began to engage them with machine guns from a defilade position covered from fire by a steep dip in the ridgeline, and concealed by thick scrub.

At dawn of 24 April, the PVA intensified their attack on the 3 RAR battalion headquarters' perimeter, killing and wounding the bulk of the Medium Machine Gun section and the Assault Pioneer Platoon and driving them off the higher ground they had been occupying, although A Company remained in full command of the hill.

The departure was successfully completed, and with 3 RAR Headquarters Company finally assembled inside the Middlesex perimeter, Gerke was then ordered to secure a key ford across the Kapyong River, 2 km (1.2 mi) east, as a possible withdrawal route for the battalion should it later have to retire from Hill 504.

Rather, using a tactic known as 'one-point-two sides', they used massed forces and infiltration to achieve local numerical superiority and to penetrate the gaps between the forward companies, before attempting to envelop the 3 RAR while drawing their fire to the front, away from their threatened flanks.

[65] Ammunition, food, and medical supplies were now extremely low throughout the forward area and with casualty evacuation increasingly difficult, the battalion was at risk of being overrun unless it could be concentrated, resupplied and supported.

The Middlesex position lay a further one km (0.62 mi) south-west of the foot of the ridge and could be reached by the ford secured earlier by Gerke, which would act as the battalion check point for the withdrawal.

The 3 RAR were fortunate, and due to difficulties of communication and navigation along the ridge line in the dark, elements of A Company had become separated and the last two platoons descended to the river too early to strike the ford.

[106] This provided Stone with an essential supply route and the ability to maneouvre 12 M3 Half-tracks carrying heavy machine guns and mortars up to the summit of Hill 677, which he then positioned adjacent to his battalion headquarters.

[92] Stone and 2 PPCLI could no longer expect that 27th Brigade HQ forces would continue to engage the enemy or would assemble a relief column to break through the PVA stranglehold on the supply road at Tungmudae.

[119] Although the initial moves were beaten back by medium machine gun fire and mortars, a second PVA assault an hour later succeeded in overrunning the right forward section of 6 Platoon.

[120] In this first wave of mass assaults of the PVA, the 2 PPCLI 60 mm (2.4 in) mortars had proven vital, their stability allowing for rapid fire out to 1,800 m (2,000 yd) with an ability to accurately hit narrow ridgelines at maximum range.

[128][129][page needed] This force assembled quietly without the usual PVA bugle and sound signals, and then moved en masse toward Stone's battalion headquarters, apparently according to a preconceived plan of attack.

[131] PVA success on this flank was intended to provide a spacious staging area to assemble an overwhelmingly large force for a final assault against the 2 PPCLI battalion HQ and principal machine gun/mortar positions.

By dawn, the attacks on the 2 PPCLI positions had abated, and with D Company remaining in control of the left flank, they were able to recover the previously abandoned machine gun at first light in daring fashion.

Private Kenneth Barwise, who had personally killed six enemy soldiers while carrying ammunition resupply during the mass assaults on D Company, now ran down through no-man's-land to the abandoned Vickers medium machine gun.

[133] Having left their supplies of food and ammunition far behind during the advance two days earlier, the PVA 118th and 60th Divisions had withdrawn back up the Kapyong Valley in the late afternoon of 25 April in order to regroup and replenish following the extremely heavy casualties incurred during the fighting.

Some PVA soldiers were now tired, hungry, and short of equipment and during the fighting at Hill 504 they had demonstrated a greater willingness to surrender than in previous encounters, with 3 RAR taking 39 prisoners, only eight of them wounded.

Contingent on the rapid attainment of its objectives, the attempted PVA coup de main ultimately failed amid heavy casualties and they abandoned their attacks against US I and IX Corps.

[180][181] After protracted negotiations between the governments of Australia, Britain, Canada, India, New Zealand and South Africa, an agreement had been reached to establish an integrated formation with the aim of increasing the political significance of their contribution, as well as facilitating the solution of the logistic and operational problems faced by the various Commonwealth contingents.

[182] For many of the 3 RAR, Kapyong was to be their last major battle before completing their period of duty and being replaced, having endured much hard fighting, appalling weather, and the chaos and confusion of a campaign that had ranged up and down the length of the Korean Peninsula.