Italian declaration of war on the United States

Declaration of war on the United States
Mussolini announces the declaration of war
Presented11 December 1941 (11 December 1941)
LocationPalazzo Venezia, Rome, Italy
Author(s)Benito Mussolini
PurposeDeclaring war on the United States so that "Fascist Italy and Nationalist Socialist Germany" would "participate from today on the side of...Japan"
Full text
Italian declaration of war on the United States at Wikisource

On December 11, 1941, Italy declared war on the United States. The declaration followed the Japanese attack on Pearl Harbor four days earlier, and came the same day as Germany's declaration of war against the United States. Benito Mussolini publicly made the announcement in Rome on December 11. Shortly before Mussolini's speech, Italian Foreign Minister Galeazzo Ciano delivered the news to the head U.S. diplomat in Italy, George Wadsworth II.

The Italian, German, and Japanese governments had all signed the Tripartite Pact in 1940, formally allying the three powers with one another. Italy and Germany also signed the Pact of Steel military alliance in 1939. Italy had declared war on the United Kingdom and France on June 10, 1940, as Mussolini implemented the Pact of Steel and leveraged the German alliance to win advantages for Italy. Prior to Hitler's declaration of war against America there was little, if any, doubt that Italy would once again "follow Germany's lead."

The United States Congress immediately responded by declaring war on Italy and Germany, bringing the United States into the Second World War and involving it in both the European and Pacific theaters of the conflict.