The evacuation of the Japanese puppet state of Manchukuo occurred during the Soviet invasion of Manchuria in August 1945, part of the last phase of World War II.
The Soviets recovered territory which had been captured by Japan during the Russo-Japanese War of 1904–1905, and they dismantled the Manchurian industrial infrastructure. This deprived Chiang Kai-shek's troops of a vital region of China, and gave Mao Zedong's Eighth Army the opportunity to establish bases in North East China.
Kwantung Army strength
On August 10, 1945, troops of the 17th Japanese Front (in Korea) and the Fifth Air Army were placed under the command of the Kwantung Army. At this point, the Japanese Kwantung Army numbered nearly 750,000 officers and men. It had 1,155 tanks and self-propelled guns, 1,800 warplanes, and 30 warships and gunboats. The entire Japanese force deployed in Manchuria, Inner Mongolia, and Korea numbered over one million officers and men.
Soviet military operations in Manchukuo and Korea
The Soviet Army possessed 1.7 times more Infantry, 4.5 times more armor, and 2.8 times more aircraft than the Japanese. On the sea theater, Soviet naval forces, unlike Japan, had no aircraft carriers and battleships. However, the chances of those vessels appearing in the Gulf of Korea or the Japan Sea were low, since Soviet air domination was complete. The Japanese Kwantung Army, stationed in Manchuria since 1931, was the first to meet the Soviet offensive. In 1945, this army consisted of 713,000 men, of whom, according to the Japanese sources, about half were poorly trained teenaged recruits and old men, since the more experienced troops had already been sent long ago to fight the Allied forces in China and the Pacific. The Soviets, on the other hand, hand-picked their best formations from the war in Europe based on their experience against certain types of terrain and enemy defenses. The Japanese troops had almost no fuel and as a result, during the ensuing battle with the Soviets not a single plane out of a fleet of 900 was able to take off, and all 600 Japanese tanks were seized by the Soviets before they were even used.
On August 9, 1945, the Soviet Army began the Sungari Offensive. The Amur Flotilla assisted troops of the second Far Eastern Front in routing the Japanese Kwantung Army. Having crossed the Amur and Ussuri rivers with the help of the Amur Flotilla, troops from two Soviet armies and an infantry corps captured two river bridgeheads.
The Japanese army used a variety of field artillery in an attempt to stop the Red Army, but had very limited ammunition available at the front line and failed to achieve significant results against the Soviet infantry and armor pouring in from the Soviet Far East and Mongolia into Manchuria and Mengjiang.
At the same time and with gunboat support a Soviet landing party entered Fuyuan and quickly took the city. The First Brigade of river gunboats from the Amur Flotilla, having swept shipping channels, entered the estuary of the river Sungari to support the troops as they landed with artillery fire. On August 10, Soviet forces captured the Sungari Fortified District and the Tuntsiang defense center. It was here that the crew of the gunboat Sun Yatsen distinguished itself.
When Soviet forces took the Fuqing Fortified District, the gunboat, acting jointly with a detachment of armoured launches, destroyed five permanent emplacements, a munitions depot and six mortar batteries with precise artillery. At the same time, the Sun Yatsen transferred landing parties across the river and supported their land operations with artillery fire.
On August 18, troops of the 15th Army captured the Sun’u Fortified District and Sun’u City and took 20,000 Japanese officers and soldiers prisoner. On August 19, Soviet ground troops and Amur Flotilla sailors captured Sanxingdui. On August 20, in Harbin, after combat action captured by Soviet paratroopers, the first and second Amur Flotilla Brigades accepted the capitulation of Japan's Sungari Flotilla only.
Soviet air superiority was virtually total. On one occasion, Red Army pilot Jr. Lt. Miroshnichenko of the 17 IAP flying the P-63 Kingcobra shot down a Ki-43 or Ki-27 fighter while operating on the Transbaikal Front out of Mongolia. If any Japanese Army planes attempted to take off from their airdromes, Russian fighters almost instantly shot them down. Not a single plane out of a fleet of 900 was able to take off due to fuel shortages after the crushing raids of Soviet Air Force and Soviet Naval Air Service aviators on Japanese land bases and ports in Manchurian and Korean coasts. Only certain units such as the 90th Air Regiment of the 5th Air Army (based in Hebei, north China) equipped with Kawasaki Ki-48s was one of the few Japanese air units in northern China to engage the Red Army over Manchuria, although others were advanced in preparation. The air unit flew 20 sorties against the Soviets during 14 August 1945.
Paratroopers formed from crews of warships and coastal units of the Pacific Fleet landed in Ryojun and Dalian. On August 25, 17 GST seaplanes which had flown five hours from Sukhodol airport near Vladivostok landed in the Ryojun inlet with landing parties made up of Pacific seamen. On the same day, Japanese garrisons in Ryojun and Dalian laid down their arms, and the Russian Pacific navy hoisted the Soviet naval ensign over Ryojun fortress.
It was the Soviet Pacific Fleet's aviation group that opened hostilities by delivering heavy strikes against the Japanese-controlled Korean ports of Yuki, Rashin and Seishin, which served as the Japanese naval bases in North Korea. These naval air arm flew a total of 474 sorties and lost 57 aircraft, 37 to enemy action, and 55 men - 23 pilots and 32 crew members. As a result of Soviet airstrikes, Japan's sea communications were cut during the first days of the war.
Between these strikes came the next operations: in a torpedo strike, Major G. D. Popovich flew an Il-4 twin-motor torpedo bomber of the 4 MTAP and sank the only Japanese naval vessel lost during the campaign, a 740-ton "Type D escort Frigate", hull number 82 (top speed 17.5kts, 2 120mm & 6 25mm guns). The Escort Vessel Type "D" Kaibokan (Escort frigate) (IJN Escort CD-82) was commanded by Reserve Lt Mori Takeshi and arrived at Genzan (now Wonsan), Korea at 6 August 1945. Between the first missions, the CD-82 departed Genzan to rescue the survivors from the 5462-ton Rashin Maru, torpedoed by USS Pargo (SS-264). During August 9, 1945, CD-82's observers saw two twin-engine Ilyushin Il-4T torpedo bombers, flying near the north east Korean coast. The escort arrived at the scene of Rashin Maru's sinking but no survivors were found. The CD-82 was suddenly targeted by two torpedo bombers from the 49th MTAP which attempted an "anvil attack". Each of the bombers carried one 45-cm (970-kg) aerial torpedo (45-36AN), but failed in the strike against Japanese vessel. At 1300, Lt Cdr Mori canceled the search for survives and ordered the vessel to return to Genzan. After their return, the crew of CD-82 was finally informed about the outbreak of war with the Soviet Union. The escort made an overnight stop in Orang Bay, south of Chongjin.
The next day, 10 August 1945, the Kaibokan CD-82 departed Orang Bay. Lt Cdr Mori received the order to leave Rashin and escort all disposable transports to Genzan. At the same time, she sighted 6886-ton freighter Mukahi Maru which was beached in shallow water off the Korean coast after escaping from Rashin. CD-82 took the ship in tow and managed to pull it free at high tide. After learning that Rashin was under attack of the Soviet bombers, Lt Cdr Mori order the small convoy to head for Genzan. The CD-82 and Mukahi Maru were again unsuccessfully attacked by a flight of Soviet torpedo bombers while underway. Expecting new attacks, Lt Cdr Mori ordered Mukahi Maru to proceed to Genzan independently.
While the vessels were en route in the Sea of Japan, 7 miles SSW of Kumsudan, North Korea, they were spotted by a trio of Soviet Il-4T torpedo-bombers from the 49th MTAP. This squadron was on an armed reconnaissance flight led by the Regiment's XO, Major Grigori D. Popovich, based from Romanovka airfield near Vladivostok, Siberia. Maj Popovich and his wingmen attacked, but CD-82's 25-mm AA gunners shot down both planes; their torpedoes missed the ships. 2/Lt Gromakov and his two crewmen were killed, but 1/Lt Lazarev managed to ditch his plane. He and his crew swam safely ashore. Popovich, targeting the kaibokan, made a perfect approach. His navigator dropped their torpedo which hit the target in the stern. The ensuing explosion detonated her depth charges and in a few seconds CD-82 sank by the stern at 41-21N, 131-12E. The captain of Mukahi Maru decided to return to find survivors from CD-82, but twenty minutes later his vessel was attacked by a flight of three Ilyushin torpedo bombers from the same unit. All three torpedoes passed beneath the hull of the freighter.
Later the Japanese freighter returned to the scene of attack and found up 93 survivors, including the CO of Kaibokan. 117 hands were lost. Mukahi Maru arrived at Songjin port (now Kimchaek) in North Korea early in the morning on 17 August 1945 where the survivors of CD-82 were debarked.
The Soviet Navy of the Pacific between August 10–24 made the following actions: Japanese merchant Riuko Maru n°2 was captured by a group of Border Guard patrol boats near the mouth of river Vorovskaya. 405 POW were taken and the guard ship (torpedo boat) Metel sank a Japanese motor-sailing vessel with gunfire close to Seisin (today Chonjin, North Korea). The vessel appeared to have been on a mission to deliver reinforcements to the enemy garrison. Patrol boat PK-31 (MO-4 class, manned by NKVD) shelled a Japanese schooner and forced it to run aground close to Maoka (Shakalin island). The torpedo boat Metel captured the abandoned Japanese tanker Horai Maru n°14 (834 GRT), previously damaged by aircraft and grounded on 10 August. Japanese military losses included only the large auxiliary gunship (Shinko Maru n°2) that was damaged. The other victims were 3 units: a merchant, a cable-layer, and a motorboat sunk. A Soviet auxiliary minesweeper Tszcz-155 captured a Japanese schooner in Kurili islands.
On August 10, 1945, Junior Lieutenant Korshunov of the 50 OMRAP, flying a Yak-9 encountered and shot down a Kawanishi H6K Mavis over Rashin (later Najin) in the northeastern-most corner of Korea. On August 15, 1945, at 13:30 hours, 29 Pe-2 dive bombers of the 55 BAP bombed the railroad station at Ranan (later Nanam). A pair of Mitsubishi J2M fighters tried to intervene and an escorting Yak-9 of the 19 IAP shot down one of them while the other escaped. At 17:18 hours that same day, 34 Pe-2s of the 33 BAP, again escorted by the Yak-9s of the 19 IAP, attacked the station at Funei (late Nuren). Despite token opposition, a J2M was shot down; this time the pilot was identified as a Lieutenant Grib.
Soon after effective raids by Soviet aviators on Japanese bases, Pacific Fleet Commander Admiral I. S. Yumashev decided, by agreement with Marshal A. M. Vasilevsky, to make landings in Yuki, Rashin, and Seishin. On the eve of the operation, naval bombers and attack planes continued to attack those ports. At the same time, the ports were attacked from the sea by torpedo boats led by division commanders Captain K. V. Kazachinsky, Captain S. P. Kostritsky, and Lieutenant-Captain M. G. Malik. The sea and air attacks seriously weakened the defenses of the three cities, causing the Japanese to lose as many as twenty transports and other vessels.
The purpose of the Seishin Landing Operation, achieved during the first days of the war, was to capture the Japanese naval base in order to deprive the enemy of the ability to transport reinforcements, equipment, and ammunition from Japan, and also to prevent the evacuation of troops and equipment to the Japanese home islands. Seishin was a fortified district with 4,000 officers and men, protected from the sea by coastal artillery. The Pacific Fleet's intention was to make a sudden landing to capture the port's moorage line and reconnoiter enemy forces. It was planned to subsequently land the main forces, occupy the city and hold it until the arrival of the 25th Soviet Army's troops advancing along the coastline.