Columbia subject headings:
Catholic Church--Foreign relations--Holy Roman Empire.
Holy Roman Empire--Foreign relations--Catholic Church.
Holy Roman Empire--History--Henry VI, 1190-1197.
Harvard subject headings:
Church and state--Holy Roman Empire
Holy Roman Empire--History--Henry VI, 1190-1197.
Princeton subject headings:
Catholic Church--Foreign religion--Holy Roman Empire.
Holy Roman Empire--Foreign religion--Catholic Church.
Holy Roman Empire--History--Henry VI, 1190-1197.