Australia in the Korean War
No. 77 Squadron converted to P-51D Mustang fighters before arriving in Japan in February 1946 to participate in the British Commonwealth Occupation Force. Occupation duties proved uneventful, and No. 77 Squadron was preparing to leave Japan for Australia when the Korean War broke out in June 1950. 77 Sqn was immediately dispatched to Korea, where they became the first UN air unit to enter the war, primarily in ground support, combat air patrol, and escort missions.
Hill 303 massacre
Following the invasion of the South Korea by North Korea, and the subsequent outbreak of the Korean War on June 25, 1950, the United Nations decided to enter the conflict on behalf of South Korea. The United States, a member of the U.N., subsequently committed ground forces to the Korean Peninsula with the goal of fighting back the North Korean invasion and to prevent South Korea from collapsing.