Columbia subject headings:
Harvard subject headings:
Civilization, Modern--Roman influences--Congresses.
Europe--Politics and government--476-1492--Congresses.
Rome--Politics and government--Congresses.
State, The--Congresses
Princeton subject headings:
Civilization, Modern--Ancient influences--Congresses.
Europe--Civilization--Congresses.
Rome (Italy)--Civilization--Congresses.