The Soviet and Japanese tank matchup

The Soviet Manchurian offensive in August 1945 was the largest armoured action in Asia during World War II, and the resulting geostrategic changes had impacts that continue to this day. Long overshadowed in the west by the use of the atomic bomb against Hiroshima and Nagasaki, the USSR’s lightning campaign in Manchuria was one of the most unique and successful strategic operations of World War II. Led by tank and mechanized units, the Red Army overcame deserts, swamps and mountains to smash Japan’s one million strong Kwantung Army in two weeks. Although Japanese forces were weak in training and modern equipment, its units often fought fanatically, and the victory cost the Soviets 32,000 casualties. Red Army operations were characterized by surprise, speed and deep manoeuvres by tank-heavy forces employing the armoured vehicles, organizations and doctrine developed at great cost fighting the Wehrmacht.

Soviet tanks and self-propelled guns (SPGs) played the decisive role in the offensive. The attack was led by battle-hardened tank and mechanized corps recently arrived from central Europe and tank brigades that had been stationed in the Far East during the war years to deter Japanese attack. The major tank formation arriving from the west, the 6th Guards Tank Army, left its battle-worn tanks in central Europe and entered battle against the Japanese with newly produced T-34s from the Ural factories and new lend-lease M4A2 Shermans. The tank brigades in the Far East had a mix of T-34s and 1930s-era BT-5s, -7s and T-26s. As a result, the Manchurian campaign would feature a unique array of pre-war tanks operating alongside the T-34-85s, Su-100s and ISU-152s developed to defeat the Wehrmacht.

The Soviets faced a large but poorly trained and equipped opponent in Manchuria. The Kwantung Army had been Japan’s premier ground force, but during the war became a source of reinforcements for other theaters. In early 1945 ten divisions departed for the defence of the home islands. The 2nd Armoured Division was sent from Manchuria to the Philippines in 1944, and the 1st Armoured Division to the home islands in early 1945. By August 1945 the Kwantung Army in Manchuria and the garrison in Korea contained 31 infantry divisions and nine infantry, and two tank brigades organized into the 3rd and 1st Area Armies, equivalent to a western army group, and the 4th Separate Army. The Japanese rated the combat power of the 24 divisions in Manchuria as equal to 7–8 full strength divisions, and the seven in Korea as equal to two. The Kwantung Army contained only two tank brigades, the 1st and the 9th, as well as scattered tank companies with some infantry divisions. Two of the brigades’ four tank regiments had been formed days before the Soviet attack.

Given the lack of Japanese armour, infantry support was the primary task for the Soviet tank and SPG force in Manchuria. Even the 1930s-era T-26s and BT-5/7s had a good high-explosive capability with their 45mm main gun, although along with the Su-76M SPG their light armour was only proof against small-arms fire. T-34s, either in the 76mm- or 85mm-armed versions had armour which could withstand almost any Japanese fire, and their primary armament had an excellent HE capability against soft targets or enemy fortifications. The preeminent armoured asset for infantry support was the ISU-152, nine regiments of which supported the First Far Eastern Front’s assault against the Japanese fortified zones in the east. Its heavy armour and 152mm howitzer were a devastating combination, and the 1st Red Banner and 5th Armies’ infantry-engineer assault teams typically included two ISU-152s for fire support.

After the war, Japanese officers identified their inability to defeat Soviet armour as a key weakness in Manchuria. The limited numbers of Type 97 mediums and Type 95 lights were matched by the T-26s and BTs, and completely outclassed by the T-34-76s and other late-war Soviet tanks and SPGs. On 12 August, in a rare tank-against-tank action, a hastily formed company of nine Type 95 light tanks engaged a large force of T-34s near Mutanchiang, losing three of their number and retreating having inflicted no losses. The two Japanese tank brigades were held in reserve in the central plain and never engaged by the Soviets, who captured 369 tanks after the surrender.

The 11th Tank Regiment stationed in the Kurile Islands was the only major Japanese armour unit to engage in combat. The clash was on Shimushu, only 2.5 kilometers from southern Kamchatka and strongly defended by 8,500 troops and the 11th Tank Regiment with 39 Type 97 medium and 25 Type 95 light tanks. The first wave of Soviet landing troops was pinned down, but the Japanese tank counterattack, led by the regimental commander waving a sword and flag in a lead tank, was defeated by Soviet troops using their PTRD-41 14.5 anti-tank rifles, anti-tank guns, and RPG-43 anti-tank grenades. The 11th lost 21 Type 95s and 97s. The Soviets reinforced the landing party and the Japanese surrendered on 23 August. The remaining Kuriles were occupied by Soviet landing parties without resistance, with the last secured by Soviet troops on 5 September.

The Japanese found that their 37mm anti-tank guns could penetrate the light armour of the T-26s and BT-5/7 tanks but were ineffective against the heavier tanks and the ISU-152 SPGs used by the First Far Eastern Front, where the most intense fighting took place. Japanese officers after the surrender recalled their anger at being able to hit T-34s with artillery but, lacking armour-piercing shells, having no effect. The Japanese were reduced to using suicide infantry attacks with soldiers throwing themselves under enemy tanks laden with explosive charges. Some of these attacks by what the Soviets dubbed smertniks (condemned men) succeeded against Soviet T-34s attacking Mutanchiang, although many of the attackers were shot down and there are also reports of the attackers carrying charges too small to disable their targets even if successfully detonated.

Su-76M loss rates during the campaign reflect the limited Japanese anti-armour capabilities. These SPGs were lightly armored and heavily used in the frontier zone and battle for Mutanchiang, but while 146 of the 952 Su-76Ms used in the campaign were listed as losses, only 20 were from enemy action. The remainder were disabled by terrain or mechanical breakdowns. Of the 146 losses, only 15 were written off and the rest returned to service.

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