The opening of the Vatican's archives for the Holocaust-era, which span the pontificate of Pope Pius XII (1939-1958), represents a generational opportunity to explore institutional Catholicism's attempts to reckon with the historical, ethical and theological implications of the Holocaust. Scholars now have access to an indispensable documentary record that will further our understanding of the role the Catholic Church played during these years. One such instance was the Holy See's clemency campaign for war criminals convicted during the Allied war crimes trials. In the early fall of 1949, Pope Pius XII instructed his nuncio in Germany to write a letter supporting clemency for convicted German war criminals to General Thomas Handy, commander of United States European Command (EUCOM). "In the spirit of centuries-old traditions, the Church seeks to have justice tempered with mercy. In accord with the time-honored prerogative of the Church to intercede for even the worst of criminals, Pope Pius XII respectfully requests that clemency be shown," wrote Pius XII's representative in Germany to General Handy on February 27, 1950. The motivations of Pope Pius XII and his advisors in clemency efforts for convicted German war criminals, most especially Catholic ones, can now be fully researched due to the new records available for the 1939-1958 period. This paper will focus on cases discovered in the Vatican Apostolic Archive, detailing the discussions between the pope, secretary of state and other senior Vatican figures on the issues war criminals.