What areas were fought over in the war fought by the Japanese Fourth Army?
Fourth Army (Japan) The Japanese 4th Army (第4軍 , Dai-yon gun ) was an army of the Imperial Japanese Army based in Manchukuo from the Russo-Japanese War until the end of World War II.
Soviet invasion of Manchuria The Soviet invasion of Manchuria, also known as the Manchurian Strategic Offensive Operation ("Манчжурская стратегическая наступательная операция" , lit. "Manchzhurskaya Strategicheskaya Nastupatelnaya Operaciya") or simply the Manchurian Operation ("Маньчжурская операция"), began on 9 August 1945 with the Soviet invasion of the Japanese puppet state of Manchukuo. It was the last campaign of the Second World War, and the largest of the 1945 Soviet–Japanese War which resumed hostilities between the Union of Soviet Socialist Republics and the Empire of Japan after almost six years of peace. Soviet gains on the continent were Manchukuo, Mengjiang (Inner Mongolia) and northern Korea. The Soviet entry into the war and the defeat of the Kwantung Army was a significant factor in the Japanese government's decision to surrender unconditionally, as it made apparent the Soviet Union would no longer be willing to act as a third party in negotiating an end to hostilities on conditional terms.