Possible Clues:

• Last Pope to be sainted
• Name of twelve Popes
• One of a dozen popes
• Apt-sounding papal name
• Eugenio Pacelli, he was Pope -- XII from 1939 to 1958
• 20's-50's papal name
• Devout pronouncement for religious leader
• Pope from Italy's more Saint
• Name of 13 popes
• Papal name last taken in 1939