On what date did the Soviet Union announce its declaration of war on Japan in 1945?

The Soviet Union announced its declaration of war on Japan on August 8, 1945.

Soviet Foreign Minister Vyacheslav Molotov informed Japan’s ambassador Naotake Satō in Moscow on August 8 that the Soviet Union considered itself at war with Japan from August 9. Soviet forces began their invasion of Japanese-held Manchuria just after midnight on August 9 in the region’s local time.

The Soviet entry had been anticipated by the Allies. At Yalta in February 1945, Joseph Stalin had agreed that the Soviet Union would enter the Pacific war within three months of Germany’s defeat. The Soviet attack therefore occurred alongside the final crisis surrounding Japan’s surrender.

The date is often confused with August 9 because fighting began on that date. It is also sometimes overshadowed by the atomic bombing of Nagasaki, which occurred on the same day as the Soviet offensive began.