The gradual disuse of Latin has its origin in the practical—though not formal—solution of the continuity between Rome and the East, which began with the division of the empire between the sons of Constantine and became more complete after Odoacer made himself King of Italy in 476. In the course of a century and a half the Latin element in the East, cut off from the Latin-speaking West, was bound to yield before the predominant Greek. But the process would have been slower if the Eastern provinces which spoke Latin had not been those which suffered most from the barbarians. The Visigoths and Ostrogoths harassed and decimated the Thracians, Illyrians, and Moesians, but the Slavs a century later almost exterminated them. In A.D. 400 probably a quarter of the provincials east of the Adriatic spoke Latin; in A.D. 620 not a tenth. The Romanized lands of the Balkan peninsula had now become Slavonic principalities: only the Dalmatian seaports and a few scattered survivors in the Balkans still used the old tongue. The only districts where a considerable Latin-speaking population obeyed the Emperor were Africa and the Italian Exarchate, now reunited to Constantinople by the conquests of Justinian. But they seem to have been too remote from the centre of life and government to have exercised any influence or delayed the de-Romanizing of the East. The last notable author, who being a subject of the empire wrote in Latin as his native tongue, was the poet Flavius Corippus who addressed a long panegyric to Justinus II.: as might have been expected, he was an African.