Event

German declaration of war against the United States

official declaration of war by the German Empire on the United States

Nazi Germany declared war against the United States on December 11, 1941, four days after the Japanese attack on Pearl Harbor and three days after the United States declared war on Japan. German officials said they were responding to a "series of provocations" by the United States when it was still officially neutral during World War II. Adolf Hitler made the decision after two days of consultation with Göring, Keitel, Raeder and German Foreign Minister Joachim von Ribbentrop, all of whom advised him to immediately declare war in view of the publication of the secret U.S. war plan Rainbow Five, and so the Kriegsmarine could begin the Second Happy Time. It has been referred to as Hitler's "most puzzling" decision of World War II.

The formal declaration was made by Ribbentrop in his office to American Chargé d'affaires Leland B. Morris. That same day, Benito Mussolini announced Italy's declaration of war on the United States the U.S. declared war on Germany. Germany's declaration eliminated any remaining meaningful domestic isolationist opposition to the U.S. joining the European war.

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