Columbia subject headings:
Alexius I Comnenus, Emperor of the East, 1048-1118.
Byzantine Empire--Foreign relations--Islamic Empire.
Islamic Empire--Foreign relations--Byzantine Empire.
Harvard subject headings:
Princeton subject headings:
Alexius I Comnenus, Emperor of the East, 1048-1118.
Byzantine Empire--Foreign relations--Islamic Empire.
Islamic Empire--Foreign relations--Byzantine Empire.