Columbia subject headings:
Europe--Kings and rulers.
Franks--History.
Papacy (International law)
Papal States--Foreign relations--History.
Papal States--Foreign relations.
Harvard subject headings:
Europe--Kings and rulers--History.
Franks--History
Papacy (International law)
Papal States--Foreign relations--History.
Princeton subject headings:
Europe--Kings and rulers.
Franks--History.
Papacy (International law)
Papal States--Foreign relations--History.