Battles of Khalkhin Gol - May, June, and July Actions

May, June, and July Actions

The incident began on 11 May 1939. A Mongolian cavalry unit of some 70–90 men had entered the disputed area in search of grazing for their horses. On that day, Manchukuoan cavalry attacked the Mongolians and drove them back across the Khalkhin Gol. On 13 May, the Mongolian force returned in greater numbers and the Manchukoans were unable to dislodge them.

On 14 May, Lt. Col. Yaozo Azuma led the reconnaissance regiment of 23rd Infantry Division, supported by the 64th Infantry Regiment of the same division, under Colonel Takemitsu Yamagata, into the territory and the Mongolians withdrew. Soviet and Mongolian troops returned to the disputed region, however, and Azuma's force again moved to evict them. This time things turned out differently, as the Soviet-Mongolian forces surrounded Azuma's force on 28 May and destroyed it. The Azuma force suffered eight officers and 97 men killed and one officer and 33 men wounded, for 63% total casualties. The commander of the Soviet forces and the Far East Front was Comandarm Grigori Shtern from May 1938.

Both sides began building up their forces in the area: soon Japan had 30,000 men in the theater. The Soviets dispatched a new Corps commander, Comcor Georgy Zhukov, who arrived on 5 June and brought more motorized and armored forces (I Army Group) to the combat zone. Together with Zhukov arrived Comcor Yakov Smushkevich with his aviation unit. And as deputy commander of G. K. Zhukov appointed Corps Commissar of Mongolian Peoples Revolutionary Army J. Lkhagvasuren.

On 27 June, IJAF's 2nd Air Brigade (2nd AB) struck the Soviet air base at Tamsak-Bulak in Mongolia. The Japanese won this engagement, but the strike had been ordered by the Kwangtung Army without getting permission from Imperial Japanese Army headquarters in Tokyo. In an effort to prevent the incident from escalating, Tokyo promptly ordered the Japanese Army Air Force to not conduct any more air strikes against Soviet airbases.

Throughout June, there were continuing reports of Soviet and Mongolian activity on both sides of the river near Nomonhan, and small-scale attacks on isolated Manchukoan units. At the end of the month, the commander of the Japanese 23rd Infantry Division, Lt. Gen. Michitarō Komatsubara, was given permission to "expel the invaders". The Japanese plan was for a two-pronged assault. Three regiments plus part of a fourth, including three from the 23rd Division—the 71st and the 72nd Infantry Regiments, plus a battalion of the 64th Infantry Regiment—and the 26th Infantry Regiment under Colonel Shinichiro Sumi, borrowed from the 7th Infantry Division, would advance across the Khalkin Gol, destroy Soviet forces on Baintsagan Hill on the west bank, then make a left turn and advance south to the Kawatama Bridge. The second prong of the attack would be the task of the IJA 1st Tank Corps (1st TC) (Yasuoka Detachment), consisting of the 3rd and 4th Tank Regiments, plus a part of the 64th Infantry Regiment, a battalion from the 28th Infantry Regiment, detached from the 7th Infantry, 24th Engineer Regiment, and a battalion from the 13th Field Artillery Regiment, all under the overall command of Lieutenant General Yasuoka Masaomi. This force would attack Soviet troops on the east bank of the Khalkhyn Gol and north of the Holsten River. The two Japanese thrusts would meet on the wings.

• Lt. Gen. Yasuoka Masaomi, IJA, Commanding Officer, 1st Tank Corps

• • 3rd Tank Regiment
    • Type 89 I-Go medium tanks - 26
    • Type 97 Chi-Ha medium tanks - 4
    • Type 94 tankettes - 7
    • Type 97 Te-Ke tankettes - 4

• • 4th Tank Regiment
    • Type 95 Ha-Go light tanks - 35
    • Type 89 I-Go medium tanks - 8
    • Type 94 tankettes - 3

The northern task force succeeded in crossing the Khalkhyn Gol, driving the Soviets from Baintsagan Hill, and advancing south along the west bank. However, Zhukov, perceiving the threat, launched a counterattack with 450 tanks and armored cars. The Soviet armored force, despite being unsupported by infantry, attacked the Japanese on three sides and nearly encircled them. The Japanese force, further handicapped by having only one pontoon bridge across the river for supplies, was forced to withdraw, recrossing the river on 5 July. Meanwhile, the 1st Tank Corps of the Yasuoka Detachment (the southern task force) attacked on the night of 2 July, moving in the darkness to avoid the Soviet artillery on the high ground of the river's west bank. A pitched battle ensued in which the Yasuoka Detachment lost over half its armor, but still could not break through the Soviet forces on the east bank and reach the Kawatama Bridge. After a Soviet counterattack on 9 July threw the battered, depleted Yasuoka Detachment back, it was dissolved and Yasuoka was relieved.

The two armies continued to spar with each other over the next two weeks along a four km (2.5 miles) front running along the east bank of the Khalkhyn Gol to its junction with the Holsten River. Zhukov, whose army was 748 km (465 mi) away from its base of supply, assembled a fleet of 2600 trucks to supply his troops, while the Japanese suffered severe supply problems due to a lack of similar motor transport. On 23 July, the Japanese launched another large-scale assault, sending the 64th and 72nd Infantry Regiments against Soviet forces defending the Kawatama Bridge. Japanese artillery supported the attack with a massive barrage that consumed more than half of their ammunition stores over a period of two days. The attack made some progress but failed to break through Soviet lines and reach the bridge. The Japanese disengaged from the attack on 25 July due to mounting casualties and depleted artillery stores. They had suffered over five thousand casualties to this point but still had 75,000 men and some hundred planes facing the Soviet forces. The battle drifted into stalemate.