Columbia subject headings:
Harvard subject headings:
Europe--Civilization--Congresses.
Europe--Social conditions--Congresses.
Europe--Social conditions--To 1492--Congresses.
Social classes--Europe--History--Congresses.
Social conflict--Europe--History--Congresses.
Social history--16th century--Congresses.
Social history--Medieval, 500-1500--Congresses
Princeton subject headings:
Civilization, Medieval.
Social conflict--Europe--History.
Space (Architecture)--Social aspects--Europe--History.