Imperial Edict Declaring War on the United States and the British Empire

What it is

This is the official Japanese declaration of war against the United States and the British Empire, published on 8 December 1941, about 7.5 hours after the attack on Pearl Harbor and strikes in Malaya, Singapore and Hong Kong. It was issued in the name of the Emperor and printed on the front page of Japanese newspapers.

Why it matters

As Prime Minister, Hideki Tojo and his government bore legal responsibility for this declaration. The text blames the United States and Britain for forcing Japan into war through economic pressure, while presenting Japan's expansion in Asia as self-defense. It reveals how the government justified aggression in official language and connected it to imperial authority.

Look closer

• How does the document describe the actions of the United States and Britain before the war?
• Why might the government want to repeat this declaration every month during the war?
• What does the document not mention about Japan's invasions of other countries?