23rd Division

The 23rd Division (第二十三師団, Dai-nijūsan Shidan) was formed on April 4, 1938 in Kumamoto as part of the military expansion during the Second Sino-Japanese War.

The division is primarily remembered for the Nomonhan Incident (ノモンハン事件, also known as the Battles of Khalkhin Gol), fought from May to September 1939 on the Mongolian-Manchurian border. The 23rd Division, assigned to the Kwantung Army's 6th Army, was the core Japanese ground force in the conflict. The battle began as a border skirmish but escalated dramatically when Soviet forces under General Georgy Zhukov launched a massive combined-arms offensive in August 1939. Soviet tanks, motorized infantry, and artillery overwhelmed the Japanese forces, who lacked adequate anti-tank weapons and mechanized support. The 23rd Division was all but destroyed: by the ceasefire of 16 September it had suffered 11,958 casualties (counting replacements) — roughly 70 to 80 percent of the men it committed. The division was later rebuilt, sent to the Philippines, and fought on Luzon from the American landings at Lingayen Gulf in January 1945 until the end of the war. The defeat profoundly influenced Japan's strategic decision to avoid further conflict with the USSR and instead strike south into Southeast Asia.