Columbia subject headings:
Christian heresies--History--Middle Ages, 600-1500.
Christian pilgrims and pilgrimages--Europe--History--To 1500.
Persecution--Europe--History--To 1500.
Harvard subject headings:
Albigenses--History
Christian heresies--History--Middle Ages, 600-1500
Christian pilgrims and pilgrimages--Europe--History--To 1500.
Crusades--History.
Europe--Church history--600-1500.
Persecution--Europe--History--To 1500.
Princeton subject headings: