name of 12 popes: especially II (Enea Silvio Piccolomini orAeneas Silvius i-ˈnē-əs-ˈsil-vē-əs orSylvius ˈsil-vē-əs ) 1405–1464 (pope 1458–64); VII 1742–1823 (pope 1800–23); IX 1792–1878 (pope 1846–78); X 1835–1914 (pope 1903–14); XI (Ambrogio Damiano Achille Ratti) 1857–1939 (pope 1922–39); XII (Eugenio Pacelli) 1876–1958 (pope 1939–58)