Gyeongui Line (1904–1945)
Following Japan's defeat in the Pacific War and the subsequent partition of Korea, the Gyeongui Line was divided at the 38th parallel between North and South Korea. On 25 August 1945, the Soviet Army began operating trains on the line north of Sariwon, whilst trains in the south terminated at Gaeseong. In 1946, the railways in both North and South were nationalised, creating the Korean National Railroad in the South and the Korean State Railway in the North. After the Korean War, the Gyeongui Line was split into three sections. In the South, the Seoul–Jangdan section became the KNR's Gyeongui Line, retaining the same name; in the North, the Bongdong–Pyeongyang section became the P'yŏngbu Line, whilst the Pyeongyang–Sinuiju section became the P'yŏngŭi Line.
North Korea–South Korea relations
The Korean peninsula had been occupied by Japan from 1910. On August 9, 1945, in the closing days of World War Two, the Soviet Union declared war on Japan and advanced into Korea. Though the Soviet declaration of war had been agreed by the Allies at the Yalta Conference, the US government became concerned at the prospect of all of Korea falling under Soviet control. The US government therefore requested Soviet forces halt their advance at the 38th parallel north, leaving the south of the peninsula, including the capital, Seoul, to be occupied by the US. This was incorporated into General Order No. 1 to Japanese forces after the Surrender of Japan on August 15. On August 24, the Red Army entered Pyongyang and established a military government over Korea north of the parallel. American forces landed in the south on September 8 and established the United States Army Military Government in Korea.