On the 25th June 1950 North Korea crossed the border into South Korea. Within two days, the US had offered air and sea support to South Korea, and the United Nations Security Council asked all its members to assist in repelling the North Korean attack. Twenty-one nations responded by providing troops, ships, aircraft and medical teams. Australia's contribution included 77 Squadron of the RAAF and the 3rd Battalion, Royal Australian Regiment (3 RAR)

When 3 RAR arrived in Pusan on 28 September, the North Korean advance had been halted and their army was in full retreat. The Supreme Commander of the UN forces, General Douglas MacArthur, was given permission to pursue them into North Korea, despite warnings from the Chinese government that it would not countenance any UN troops crossing the border.

At the same time, unbeknown to the UN commanders, the Chinese government had made good its threat and moved 18 divisions into North Korea. They struck with overwhelming force against US troops on 1 November and sent them into retreat. By mid-November, despite the continuing Chinese attacks in the harsh winter weather, MacArthur prepared a massive advance to the Yalu River to defeat the North Korean and Chinese forces once and for all. But only one day after the attack commenced the Chinese struck back, inflicting successive defeats on the UN forces and forcing them into retreat towards the 38th parallel.

From 1951 on, both sides found themselves engaged in a war of attrition reminiscent of the Western Front, where men lived in tunnels, redoubts and sandbagged forts behind barbed wire defences. The war was generally fought with artillery and mines and in set-piece battles; at night patrols ventured into no man's land to raid enemy positions.

As the war settled into stalemate it became apparent that a negotiated truce was the only solution. After two years and 17 days of negotiations, the UN and North Korean leaderships signed an agreement on 27 July 1953. This agreement technically brought the war to an end, but a state of suspended hostilities continued to exist between North and South Korea for many years, and even today the situation remains unresolved. AWM

The Australian Army suffered 1,538 casualties in Korea. Of these 281 were killed and missing. Total United Nations casualties were estimated at 73,500 men KIA. The South Koreans fared worst-with 45,000 KIA. The Americans had 25,600 KIA and other UN member nations lost 3,094 dead.