In the late middle ages and the early centuries of the Turkish period the common spoken language of the Byzantine empire lived on, but tended more and more to become regionally differentiated. It was impoverished in abstract terms and ill-adapted to serve as a vehicle of higher culture. The Greek upper classes of Constantinople and of other cities in the Ottoman empire, and the Orthodox church, used for all official and literary purposes the traditional learned language, which was essentially late Atticising Koine. New literary languages, based upon the dialects of particular regions but strongly influenced by the common spoken language began to be formed in parts of the Greek world where the conditions favoured an active cultural life. The only one of these to attain any degree of maturity was that of the Cretan literature of the sixteenth and seventeenth centuries. But even in Crete the favourable conditions did not last long enough for a national language, parallel to those of western Europe, to arise.

In the second half of the eighteenth century the political and intellectual prospects of the Greek subjects of the Ottoman empire changed dramatically. The influence of the European Enlightenment – often channelled through the University of Padua or through the academies established by the rulers of the Danubian Principalities of Moldavia and Wallachia – and the example of the French, and to a lesser extent of the American, Revolution put the questions of political liberty and of freedom of thought and expression on the order of the day.