Columbia subject headings:
Papacy--History--To 1309.
Rome (Italy)--Church history--Middle Ages, 600-1500.
Rome (Italy)--Church history.
Harvard subject headings:
Papacy--History--To 1309
Princeton subject headings:
Church and state--Europe--Catholic Church.
Church history--Middle Ages, 600-1500.
Church history--Primitive and early church, ca. 30-600.
Papacy--History--To 1309.
Popes--Primacy.