Columbia subject headings:
Europe--History--392-814.
Migration, Internal--History--To 1500.
Migrations of nations.
Transportation--History--To 1500.
Harvard subject headings:
Europe--History--392-814.
Migration, Internal--History--To 1500.
Migrations of nations.
Transportation--History--To 1500.
Princeton subject headings:
Europe--History--392-814.
Migration, Internal--History--To 1500.
Migrations of nations.
Transportation--History--To 1500.