SOVIET UNION DECLARES WAR ON JAPAN

Moscow, Soviet Union August 8, 1945

On this date the Soviet Union declared war on Japan, the last Axis hold-out after the Soviets and their Western Allies had van­quished Nazi Germany and Fascist Italy. U.S. Presi­dent Frank­lin D. Roose­velt and British Prime Mini­ster Win­ston Chur­chill had long urged Soviet Premier Joseph Stalin to join the West in tightening the noose around the necks of Tokyo’s war­lords. Stalin’s hand on the hemp necktie in exchange for guar­an­tees of Far East­ern booty agreed to at two Big-Three Con­fer­ences (Novem­ber 1943 and Febru­ary 1945) pushed the ava­ri­cious Soviet dicta­tor in April 1945 to tell Japan’s leaders that he would not be extending their coun­tries’ mutual neu­tral­ity pact, which still had a year to run. While Stalin furiously worked to strengthen his mili­tary presence in the Far East by shifting an addi­tional 40 Soviet divi­sions along with some 500 new Sher­man tanks, a gift from the United States, to the Mongo­lian and Man­chu­rian borders, his diplo­mats assured the ner­vous Japa­nese they had nothing to worry about during the next 12 months.

Stalin’s duplicitous game doomed Japan’s hope that the Soviets would act as a disin­ter­ested third party in nego­ti­a­ting an end to hos­til­i­ties short of uncon­di­tional sur­ren­der as demanded by the Western powers. Now Japa­nese war plan­ners looked at their calen­dars to fore­cast when the Soviet on­slaught would strike Japan’s puppet state on the Chi­nese main­land, Man­chu­kuo (Man­chu­ria). August or Septem­ber maybe, or even early 1945? Psycho­log­i­cally and mili­tarily Japan was no­where near pre­pared for a mas­sive Soviet inva­sion of its mainland and ancillary possessions.

On August 9, 1945, the Soviets began their Manchu­rian offen­sive (Soviet name, Man­chu­rian Stra­tegic Offen­sive Oper­a­tion; in the West, Oper­a­tion August Storm). It was a gigan­tic pincer move­ment by three fronts, the equiv­a­lent of 3 West­ern army groups. Land and air forces con­sisted of 1.5 mil­lion well-armed, battle-hardened men from Europe’s Eastern Front: 76 or 89 divi­sions equipped with 3,704 or 4,500 tanks, 1,852 self-pro­pelled guns, 85,819 vehi­cles, and 3,721 or 4,300 air­craft (sources differ for every listed cate­gory). Naval forces con­sisted of 12 major sur­face ves­sels, 78 sub­marines, numer­ous amphib­ious craft, and a river flotilla of gunboats and small craft.

Soviet forces easily swept aside Japan’s depleted Kwan­tung Army of occu­pa­tion and its second-rate Man­chu­kuoan allies. In the case of Man­chu­kuoan sol­diers, many melted away into the inte­ri­or or mutinied rather than defend Japa­nese con­voys and Man­chu­rian, North­east Chin­ese, and Korean terri­tories. Most of the Kwan­tung Army’s best armored and elite infan­try units, along with heavy mili­tary equip­ment, modern anti­tank wea­ponry, and stocks of ammu­ni­tion, were absent from the main­land, having been trans­fer­red to the Paci­fic Thea­ter over the pre­vious 3 years in a futile attempt to reverse the tide of Allied victories.

By August 21, 1945, the Red Army had secured the ulti­mate objec­tives of its cam­paign, including Chang­chun (Xin­jing or Hsin­king during Japan’s occu­pa­tion), capi­tal of Man­chu­kuo and head­quarters of the Kwan­tung Army. The Japa­nese High Com­mand had already announced the capit­u­la­tion of the Kwan­tung Army 5 days ear­lier. For all prac­ti­cal pur­poses, orga­nized resis­tance ceased after August 21. What remained was collecting pri­soners, dis­arming Japa­nese and Man­chu­kuo units, and occupying central and southern Manchuria.

With Japan’s Septem­ber 2, 1945, sur­render pending, the Red Army staked claims to half the Korean Penin­sula. The Soviets dis­patched some 8,000 sol­diers across 500 nau­ti­cal miles/­926 km of sea to the Kuril archi­pel­ago, where com­bat oper­a­tions ended on August 21. Sak­halin Island oppo­site Soviet Siberia, which Japan and the Soviet Union shared, was secured on August 26. In Man­chu­ria and the island oper­ations, the Soviets claimed to have killed, wounded, or cap­tured 674,000 Japa­nese troops at a cost to the Red Army of 12,031 dead and 24,424 sick or wounded. Japan claimed 21,389 killed, but the true figure likely exceeds 80,000.

Catching Japan Unawares: Sudden Soviet Strike in August 1945 Ends Manchukuo’s Short Existence

Map of Soviet Union's 1945 Invasion of Manchuria

Above: Map showing most of the extent of Opera­tion August Storm (August 9–20, 1945), known by the Soviets as the Man­chu­rian Stra­tegic Offen­sive Oper­a­tion or more simply as the Man­chu­rian Oper­a­tion. The invading forces pri­marily tar­geted Japanese-occupied Man­chu­ria (Japanese-puppet state of Man­chu­kuo), an area of 600,000 sq. miles/­1.55 bil­lion sq. km in North­east China. Red Army forces also swept onto the Korean Penin­sula, halting at the 38th parallel (today’s boun­dary between North and South Korea), the Kuril Islands that form an archi­pelago from Hok­kaido, Japan’s northern­most home island, to the Soviet Union’s Kam­chatka Penin­sula, and the whole of Sak­halin Island oppo­site Soviet Siberia. (Captured islands not shown on this map.)

Operation August Storm: Manchukuo army recruits during rifle trainingOperation August Storm: Japanese reinforcements depart for the Manchurian front

Left: New recruits of the Japanese-trained Manchu­kuo Impe­rial Army blaze away at rifle prac­tice before being sent to the Sibe­rian border in July 1945. The army, raised from local Chi­nese collab­o­ra­tors, num­bered between 170,000 and 220,000 men at its peak in 1945 but pos­sessed neither the will nor the means to give much com­bat sup­port to the Japa­nese army of occu­pa­tion—the Kwantung Army. Sol­diers of the Man­chu­kuo Impe­rial Army, volun­teers and con­scripts, were con­sidered to be mostly unre­li­able by their Japa­nese offi­cers and advi­sers due to poor training and low morale. In the face of cascading Soviet advances in Man­chu­kuo in August 1945 a week­long series of muti­nies broke out in the capi­tal, Changchun. In revenge for the years of brutal treat­ment a num­ber of Man­chu­kuoan sol­diers killed their Japa­nese offi­cers. A minority of Man­chu­kuoan regulars and aux­il­ia­ries remained loyal and con­tinued to fight on alongside the Japanese.

Right: Japanese reinforcements depart for the Manchurian front following the Soviet inva­sion, which came several months before the Japa­nese had expected it. The Kwan­tung Army—esti­mated by the Soviets to num­ber over a mil­lion men had an actual strength of 713,724 second-line troops orga­nized into 24 in­fan­try divi­sions, 9 in­fan­try bri­gades, and 2 tank bri­gades. The so-called Man­chu­kuo Impe­rial Army num­bered 170,000 men. Also aiding the Japa­nese were 44,000 cav­alry troops in Inner Mon­go­lia. Else­where in the thea­ter—in Korea, Sakha­lin Island, and the Kurils—the Japa­nese forces numbered 289,000 men. Most of the remaining divi­sions of the Kwan­tung Army were newly formed from reser­vists, con­scripts, and troops canni­ba­lized from other units. Training was extremely limited in all units, and equip­ment and mate­rial short­ages plagued Japa­nese and collab­o­ra­tionist forces at every level.

Operation August Storm: Soviet troops invade Manchuria, August 9, 1945Operation August Storm: Operation August Storm: Soviet troops stream into captured Harbin, Manchuria, August 21, 1945

Left: Soviet troopers invade Manchuria on Day 1, August 9, 1945. Sol­diers here follow in the wake of an armored vehicle towing an artil­lery piece up a sharp incline. The Soviet inva­sion of Japa­nese-occu­pied Manchu­ria was not done as a favor to Stalin’s West­ern Allies who dearly wanted assis­tance in ending the Pacific War quickly and expe­di­tiously. Instead, it was Stalin’s modus ope­ran­di of extending Soviet mili­tary and geo­polit­ical hege­mony over new swatches of the Asia-Pacific region and reclaiming what his coun­try had lost in decades past. Stalin did it all in a Blitz­krieg reminiscent of Nazi Germany.

Right: Soldiers of the 2nd Far East Front, one of 3 Soviet Fronts (army groups) that invaded Man­chu­kuo, stream into cap­tured Harbin on August 21, 1945. In time roughly 700,000 Soviet troops occu­pied the former Japa­nese puppet state out of nearly 2 million who saw ser­vice in the Far East. Harbin, like other major popu­la­tion centers in Man­chu­ria, became a center of Soviet looting and mass rape of Japa­nese women, including under­age girls who were also con­sidered to be war spoils. Over a half-mil­lion Japa­nese troops and able-bodied Japa­nese men in Man­chu­ria were taken pri­soner and trans­ported to labor camps in Siberia, the Soviet Far East, and Mon­golia, where many would die. Some 30,700 non-Japa­nese sol­diers (chiefly Chi­nese and Koreans) also became pri­soners of war. Those who sur­vived their cap­tiv­ity were repa­tri­ated in stages over the next 5 years, though some con­tinued to be held well into the 1950s.

Soviet Colossus Nails Shut Imperial Japan’s Coffin