Title: Consequences of the attack on Pearl Harbor
Content: no alternative; in any case, had an acceptable settlement of differences been reached, the Carrier Striking Task Force could have been called back. On December 11, 1941, Nazi Germany and Fascist Italy declared war on the United States, and the United States reciprocated, formally entering the war in Europe. German dictator Adolf Hitler and Italian dictator Benito Mussolini were under no obligation to declare war on the United States under the mutual defense terms of the Tripartite Pact until the US counterattacked Japan. However, relations between the European Axis Powers and the United States had deteriorated since 1937. On December

Title: European theatre of World War II
Content: Chancellor of Germany in 1933. After Hitler took Germany out of the League of Nations, Mussolini of Fascist Italy and Hitler formed the Rome-Berlin axis, under a treaty known as the Pact of Steel. Later, the Empire of Japan, under the government of Hideki Tojo, would also join as an Axis power. Japan and Germany had already signed the Anti-Comintern Pact in 1939, to counter the perceived threat of the communism of the Soviet Union. Other smaller powers also later joined the Axis throughout the war. Germany and the Soviet Union were sworn enemies, but following the Munich Agreement, which

Title: Ion Antonescu
Content: to change their stance, the British government responded to repeated Soviet requests and declared war on all three countries. Following Japan's attack on Pearl Harbor and in compliance with its Axis commitment, Romania declared war on the United States within five days. These developments contrasted with Antonescu's own statement of December 7: "I am an ally of the [German] Reich against [the Soviet Union], I am neutral in the conflict between Great Britain and Germany. I am for America against the Japanese." A crucial change in the war came with the Battle of Stalingrad in June 1942 – February 1943,

Title: Modern history
Content: in the mean time attacked by Italy as well, surrendered to Germany, which then tried unsuccessfully to conquer Britain. On September 27, Germany, Italy, and Japan signed a mutual defense agreement, the [[Tripartite Pact]], and were known as the [[Axis Powers]].Nine months later, on June 22, 1941, Germany launched a massive invasion of the Soviet Union, which promptly joined the Allies. Germany was now engaged in fighting a war on two fronts. This proved to be a mistake by Germany – Germany had not successfully carried out the invasion of Britain and the war turned against the Axis. On December

Title: Axis powers
Content: Axis powers The Axis powers (; ; "Sūjikukoku"), also known as "Rome–Berlin–Tokyo Axis" (also nicknamed with the Italian name "Roberto", from the initials of "ROma", "BERlin" and "TOkyo"), were the nations that fought in World War II against the Allies. The Axis powers agreed on their opposition to the Allies, but did not completely coordinate their activity. The Axis grew out of the diplomatic efforts of Germany, Italy, and Japan to secure their own specific expansionist interests in the mid-1930s. The first step was the treaty signed by Germany and Italy in October 1936. Benito Mussolini declared on 1 November

Question: Which Axis Power changed sides during World War II, declaring war on Germany in October 1943?
Answer: Italy