The Kwantung Army was Japan’s major army in Manchuria defeated during the Soviet offensive of 1945.
The Kwantung Army was created in 1906 to protect Japanese interests in the Kwantung Leased Territory and the South Manchuria Railway. It later became deeply involved in the creation and defense of Manchukuo, Japan’s puppet state established in Manchuria in 1932.
By August 1945, the army still had hundreds of thousands of personnel, but many veteran troops and modern weapons had been moved to defend Japan and other fronts. Soviet forces launched a large, coordinated attack on August 9, rapidly breaking through Japanese positions and overwhelming much of the army.
The Kwantung Army’s collapse was a major military development during the surrender crisis. Its formal surrender followed Japan’s imperial announcement, although scattered fighting and local Japanese resistance continued in parts of northeast Asia until after the September surrender ceremony.