'' Main article : '' Chinese Eastern Railway At the Yalta Conference in February 1945 , the Soviet government agreed to join the war against Japan ninety days after the surrender of Nazi Germany . One condition of the Soviet Union 's agreement to enter the war against Japan was for the return of all Russian territory and property taken during the 1904-1905 Russo-Japanese War . As a result of the Yalta Agreement , upon the end of the war against Japan , the Soviet Union would regain partial control of the China Eastern Railway in the same arrangement as the original Russian concession from 1896 . The railway was to be jointly owned and operated by the Soviet Union and Republic of China . In addition , the Soviet Union would regain sovereign interest in the ports of Lüshun and Dalian , which were at the terminus of the southern branch of the Chinese Changchun Railway , the South Manchuria Railway . The Yalta Agreement stated : " The Chinese-Eastern Railroad and the South Manchuria Railroad , which provides an outlet to Dairen shall be jointly operated by the establishment of a joint Soviet-Chinese Company , it being understood that the preeminent interests of the Soviet Union shall be safeguarded and that China shall retain full sovereignty in Manchuria . " On August 9 , 1945 , the Soviet Union invaded from Soviet Outer Manchuria and soon occupied Japanese Manchukuo including the entirety of the China Eastern Railway . Shortly thereafter , the Republic of China government and the Soviet Union signed the " Agreement between the Republic of China and the Soviet Socialist Republic on the Changchun Railway of China . " This agreement recognized the joint control of the Chinese Eastern Railway and renamed the line to the Chinese Changchun Railway
Yalta Conference
Yalta Conference
Return of the Chinese Eastern Railway