Columbia subject headings:
Harvard subject headings:
France--Social life and customs--History.
Franks--History--814-843
Holy Roman Empire--History--Louis I, 814-840
Louis I, Emperor, 778-840
Princeton subject headings:
France--Social life and customs--History.
Franks--History--814-843.
Holy Roman Empire--History--Louis I, 814-840.
Louis I, Emperor, 778-840.