World War II

United States declaration of war on Japan
President Roosevelt, wearing a black armband, signs the Declaration of War on Japan on December 8, 1941 ©Image Attribution forthcoming. Image belongs to the respective owner(s).
1941 Dec 8

United States declaration of war on Japan

United States

On December 8, 1941, the United States Congress declared war on the Empire of Japan in response to that country's surprise attack on Pearl Harbor and declaration of war the prior day. It was formulated an hour after the Infamy Speech of President Franklin D. Roosevelt. Following the U.S. declaration, Japan's allies, Germany and Italy, declared war on the United States, bringing the United States fully into World War II.

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Last Updated: Mon Oct 31 2022