Columbia subject headings:
Imperialism.
Middle East--History--To 622.
Rome--Army--History.
Rome--History--Empire, 30 B.C.-476 A.D.
Harvard subject headings:
Middle East--History--To 622.
Rome--Army--History.
Princeton subject headings:
Imperialism.
Middle East--History--To 622.
Rome--Army--History.
Rome--History--Empire, 30 B.C.-476 A.D.