Using newly available material from the U.S. National Archives, Michael Phayer sheds new light on the actions of the Vatican and of the man whom some have mistakenly called "Hitler's Pope." As a new world war loomed, the Vatican believed it had to make a choice between communism and Nazism. Reluctantly, both Pius XII and his predecessor chose the Nazis as the lesser of two evils. In the balance rested the genocide of European Jews. As difficult as his wartime behavior is to accept, perhaps nothing demonstrates Pius's fear of communism more than his misguided and unethical attempt to thwart its growth in South America by abetting the escape of Nazis and Ustaši war criminals. The story of these Vatican "ratlines" adds another facet to the complex picture of Pius XII and the Holocaust.