Short answers, pulled from the story.
Organized anti-communism developed after the October 1917 Revolution in Russia. The Russian White movement, which took up arms against the Bolshevik government in 1918, was the first organization specifically dedicated to opposing communism. Foreign governments backed the Whites militarily, marking the first instance of anti-communism as an official state policy.
The Anti-Comintern Pact was an anti-communist alliance initially signed by Nazi Germany and Imperial Japan in 1936. Italy joined in 1937. Finland and Spain signed in 1941. The pact committed signatories to sharing intelligence on Comintern activities and planning joint operations against them.
Pope Pius IX called communism and socialism the most fatal error in his encyclical Quanta cura. Pope John Paul II was also a harsh critic of communism. In Italy, the Christian Democracy party founded by Alcide De Gasperi in 1943 translated papal opposition into politics, dominating Italian governance for nearly fifty years until 1993 and blocking the Italian Communist Party from reaching power.
Samizdat was a form of dissident activity across the Soviet bloc in which individuals hand-copied censored publications and passed them from reader to reader. Vladimir Bukovsky defined it as something one creates, edits, censors, publishes, distributes, and gets imprisoned for. Western countries also invested heavily in radio transmitters to reach Eastern Bloc audiences; Voice of America began Russian-language broadcasts in 1947.
The God That Failed is a 1949 book collecting six essays by famous former communists who were writers and journalists, including Louis Fischer, Andre Gide, Arthur Koestler, Ignazio Silone, Stephen Spender, and Richard Wright. The common theme is the authors' disillusionment with and abandonment of communism. Its promotional byline described it as six famous men telling how they changed their minds.
Nazi propaganda merged anti-communism with antisemitism under the label "Judeo-Bolshevism," asserting that Jews were responsible for communism. Hitler described this as "a fact proved by irrefutable evidence" in a September 1937 Nuremberg rally speech. This belief was shared by German army commanders and helped justify the systematic extermination of Jewish people as an alleged measure against communism.