Footnote

a The Latin inherited from the Roman legions, called Roman, had by that time developed into two vernacular languages in France: Southern France spoke the langue d’oc (also known as Occitan, or Provençal), while northern France spoke the langue d’oïl (an early form of French sometimes called Old French). These two languages were distinguished, one from the other, by the word they used for yes. In the south it was oc (from Latin hoc); in the north, oïl (from Latin hoc ille), which became the modern French oui.