Soviet forces invaded Manchuria on August 9, 1945, during the final phase of World War II. The campaign targeted Japanese-controlled Manchukuo and the powerful Japanese Kwantung Army.
The Soviet Union declared war on Japan late on August 8, 1945, and began its offensive just after midnight on August 9 in the Far East. Soviet armies attacked from several directions, including the east, west, and north, overwhelming Japanese defenses across a huge area.
The invasion was connected to Allied agreements made at the Tehran and Yalta conferences. The Soviet Union had promised to enter the war against Japan within three months of Germany’s defeat in Europe. Germany surrendered in May, making early August the expected deadline.
Manchuria is sometimes confused with Korea or the Japanese home islands because Soviet forces also fought in northern Korea, southern Sakhalin, and the Kuril Islands. However, the central and largest Soviet campaign was the invasion of Manchuria, which helped accelerate Japan’s decision to accept surrender terms.