Columbia subject headings:
Catholic Church--Bishops--History.
Church and state--Catholic Church--History.
Papacy--History--To 1309.
Harvard subject headings:
Catholic Church--Bishops--History.
Church and state--Catholic Church--History
Church history--Middle Ages, 600-1500
Papacy--History--To 1309
Princeton subject headings:
Catholic Church--Bishops--History.
Church and state--Catholic Church--History.
Papacy--History--To 1309.