The Anti-Comintern Pact, officially the Agreement against the Communist International was an anti-Communist pact concluded between Nazi Germany and the Empire of Japan on 25 November 1936 and was directed against the Communist International (Comintern). It was signed by German ambassador-at-large Joachim von Ribbentrop and Japanese ambassador to Germany Kintomo Mushanokōji. Italy joined in 1937, but it was legally recognized as an original signatory by the terms of its entry. Spain and Hungary joined in 1939. Other countries joined during World War II.

Anti-communism is political and ideological opposition to communist beliefs, groups, and individuals. Organized anti-communism developed after the 1917 October Revolution in the Russian Empire, and it reached global dimensions during the Cold War, when the United States and the Soviet Union engaged in an intense rivalry. Anti-communism has been an element of many movements and different political positions across the political spectrum, including anarchism, centrism, conservatism, fascism, liberalism, nationalism, social democracy, socialism, leftism, and libertarianism, as well as broad movements resisting communist governance. Anti-communism has also been expressed by several religious groups, and in art and literature.