Gyeongwon Line (1911–1945) on 1 April 1944. After the partition of Korea following the end of the Pacific War in 1945, the Gyeongwon Line was split along the 38th parallel between the stations of Hantangang and Choseongni. The railways in both South and North were nationalised, and the newly established Korean National Railroad took over operation of the truncated Gyeongwon Line, from Seoul to Choseongni; in the North, the Korean State Railway merged its section of the Gyeongwon Line, Choseongni−Wonsan, with the Wonsan−Gowon section of the former Hamgyeong Line to create the Gangwon Line. The line was severely damaged during the Korean War.
Australia in the Korean War and the United Nations Security Council asked its members to help repel the North Korean attack. Australia immediately contributed No. 77 Squadron RAAF and the 3rd Battalion, Royal Australian Regiment (3 RAR), both of which were stationed in Japan under the British Commonwealth Occupation Force (BCOF). 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,