Columbia subject headings:
Harvard subject headings:
Alexius I Comnenus, Emperor of the East, 1048-1118.
Byzantine Empire--History--Alexius I Comnenus, 1081-1118.
Civilization, Medieval
Crusades--First, 1096-1099
Princeton subject headings:
Alexius I Comnenus, Emperor of the East, 1048-1118--Early works to 1800.
Byzantine Empire--History--Alexius I Comnenus, 1081-1118--Early works to 1800.