1. Declared War on Japan: On August 8, 1945, the Soviet Union declared war on Japan, breaking the neutrality pact it had signed with Japan in 1941. This declaration marked the official entry of the Soviet Union into World War II on the side of the Allies.
2. Invaded Manchuria: In the days and weeks following the Hiroshima bombing, the Soviet Union launched a massive military operation known as the Manchurian Strategic Offensive Operation. The Soviet forces rapidly advanced through Japanese-occupied Manchuria (present-day northeast China), capturing key cities and defeating the Japanese Kwantung Army.
3. Occupied Northern Territories: As a result of its military success in Manchuria, the Soviet Union occupied several territories that had previously been under Japanese control. These territories included the Kuril Islands, southern Sakhalin Island, and parts of northern Korea.
4. Demanded Territorial Concessions: In addition to occupying these territories, the Soviet Union demanded that Japan make territorial concessions to the Soviet Union as a condition for peace. These demands included the cession of the Kuril Islands and southern Sakhalin Island, which were formally annexed by the Soviet Union in 1946.
5. Influence on Postwar Order: The Soviet Union's entry into the war and its subsequent military actions in Manchuria had a significant impact on the postwar order in East Asia. The Soviet Union's territorial gains and its increased influence in the region shaped the geopolitical landscape of the Cold War era.
It's important to note that the decision by the United States to drop atomic bombs on Hiroshima and Nagasaki was controversial, with many arguing that it was unnecessary and disproportionately destructive. The Soviet Union's entry into the war against Japan and its subsequent actions were influenced by a combination of factors, including the desire to gain territorial concessions, to expand its influence in Asia, and to hasten the end of the war on more favorable terms for the Allies.