The Vatican opened once-secret records on Pope Pius XII on March 2020. This gave researchers a brand new insight into the Catholic Church during the Nazi era. What did the Pope know about the Holocaust? Pius XII, born Eugenio Pacelli, is one of the most controversial figures in recent church history. New archive material sheds light on his career and politics. As ambassador of the Holy See in Germany and Cardinal Secretary of State of the Vatican, Pacelli witnessed Hitler's rise to power.