Columbia subject headings:
Canossa (Italy)--History--To 1500.
Catholic Church--Foreign relations--Holy Roman Empire.
Church and state--Holy Roman Empire.
Church history--Middle Ages, 600-1500.
Germany--History--Henry IV, 1056-1106.
Gregory VII, Pope, approximately 1015-1085.
Henry IV, Holy Roman Emperor, 1050-1106.
Holy Roman Empire--Foreign relations--Catholic Church.
Harvard subject headings:
Canossa (Italy)--History.
Church and state--Europe--History
Europe--Church history--600-1500.
Gregory VII, Pope, approximately 1015-1085--Political and social views.
Henry IV, Holy Roman Emperor, 1050-1106--Political and social views.
Holy Roman Empire--History--Henry IV, 1056-1106.
Investiture
Italy--Church history--476-1400.
Monasticism and religious orders--Europe--History--Middle Ages, 600-1500.
Princeton subject headings: