Columbia subject headings:
Serfdom--England--History.
Slavery--England--History.
Slaves--England--Social conditions.
Harvard subject headings:
England--Social conditions--1066-1485.
Great Britain--History--Medieval period, 1066-1485.
Labor--England--History.
Middle Ages
Serfdom--England--History.
Slavery--England--History.
Princeton subject headings:
Labor--England--History.
Middle Ages.
Serfdom--England--History.
Slavery--England--History.