Its name was derived from its exporter Romania, which was at that time a common name for Greece and the southern Balkans as the lands of the Eastern Roman Empire.
The wine was called Rumney or Romney in English, Romenier or Rumenier in German, vino di Romania in Italian.
Rumney was exported from Methoni in the southern Peloponnese (one English source calls it Rompney of Modonn) and perhaps also from Patras and other ports.
At the same period, Monemvasia, on the eastern coast of the Peloponnese, was the centre for the export of Malmsey wine; Cretan wine was the third of the medieval trio of Greek wines that were prized in western Europe.
It was not a "fortified" wine in the modern sense, rather a "cooked" wine (vin cuit) to which boiled-down must (grape syrup) was added.