On what date did Soviet forces begin their invasion of Japanese-held Manchuria?

Soviet forces began their invasion of Japanese-held Manchuria on 9 August 1945.

The invasion started shortly after midnight, following the Soviet declaration of war against Japan on 8 August. The Red Army launched coordinated offensives from the east, west, and north against Japanese forces in Manchuria, which Japan controlled through the puppet state of Manchukuo.

The campaign is often called the Soviet–Japanese War or the Manchurian Strategic Offensive Operation. Soviet and Mongolian forces used large formations of armor, artillery, and aircraft, while Japanese units were weakened by the transfer of experienced troops to other fronts. The Kwantung Army collapsed rapidly in many sectors, and Soviet advances continued into Korea, southern Sakhalin, and the Kuril Islands.

The invasion is sometimes confused with the date of the declaration of war, because the two events occurred only hours apart. The declaration was made on 8 August in Moscow time, while the military offensive began on 9 August in the region’s local time. Japan announced its willingness to accept surrender terms on 15 August.