Columbia subject headings:
Byzantine Empire--Politics and government.
Nicaea (Turkey)--Politics and government.
Harvard subject headings:
Byzantine Empire--Politics and government--1081-1453.
Nicaea, Empire of--Politics and government.
Princeton subject headings:
Byzantine Empire--Politics and government--1081-1453.
Epirus (Greece and Albania)--History--Despotate, 1204-1318.