From May 1951, the Korean War shifted from fluid movement to positional trench warfare along a heavily fortified, static front line. United Nations (UN) and communist forces fought bitter, high-casualty 'seesaw battles' over strategic positions, including Bloody Ridge, Heartbreak Ridge and Pork Chop Hill. As peace negotiations neared completion in 1953, communist troops intensified assaults to gain political leverage. Australian infantry dug trench networks and defended key positions like The Hook right up until the armistice took effect on 27 July 1953.
When their fifth offensive failed in May 1951 the communists abandoned a war of movement and engaged the United Nations Command (UNC) in positional warfare …
Limited advances against heavily fortified positions, intense artillery bombardments, trench fighting, minefields, barbed wire and aggressive patrolling characterised this phase of the Korean War.
The first clashes began when the UNC attempted to eliminate tactically important enemy-held positions.
From 18 August to 5 September 1951, South Korean (ROK) and US forces assaulted Hill 938, then held by North Korean (KPA) troops. In what became known as the Battle for Bloody Ridge, the UNC captured the objective at the human cost of 2,700 casualties. KPA losses were estimated to be 14,000.
From 13 September to 15 October, the 2nd US Division launched a series of assaults against the KPA-occupied Heartbreak Ridge. Very heavy fighting resulted in US and French troops eventually capturing the heights with 3,700 casualties. KPA and Chinese (CPV) losses were 22,000.
Fighting ‘seesaw battles’ to contest selected topographical features was a deliberate tactic employed by the CPV.
Beginning late in 1951, the 10-month struggle for a treeless mountain known as Old Baldy saw the mountain change hands several times.
In the Battle for Whitehorse Mountain from 6 to 15 October 1952, the objective changed hands 24 times before the UNC finally secured it.
The Battle for Hill 598 in the Triangle Hill area from 14 October to 25 November 1952 was also severe. The brutal 42-day engagement resulted in a defeat for the UNC, with 9,000 casualties in 42 days.
By January 1953, 758,000 UNC troops faced 1.1 million communist troops along a front line that had changed very little since May 1951.
Peace negotiations were nearing a conclusion, but the communists were determined to win the political and psychological contest. So they intensified their military efforts.
Through the first months of 1953, communist assaults steadily increased in intensity and size. In June, 3 CPV divisions drove ROK troops back 5 km.
On 6 July, the communists launched their most ambitious offensive since May 1951. By 11 July, they had captured Pork Chop Hill. On 13 July, 6 CPV divisions struck south of Kumsong, pushing ROK troops back 13 km.
UNC counterattacks won back some of the ground lost before the armistice came into effect at 10 pm on 27 July 1953.
The Hook was the site of 4 major clashes between the UNC and the CPV in 1952 and1953. The final battle for the Hook occurred just a day before the armistice took effect. It was the last battle for the 2nd Battalion, Royal Australian Regiment (2RAR).
The last 2 months of the war were among its bloodiest. It cost 53,000 UN and 105,000 communist casualties, mostly inflicted by artillery. In this same period, over 700,000 communist artillery rounds hit UNC positions, and 4.9 million UNC artillery rounds were fired in response.
