Languages of the Roman Empire

Latin and Greek were the dominant languages of the Roman Empire, but other languages were important regionally. The language of the ancient Romans was Latin, which served as the "language of power". Latin was pervasive in the Roman Empire as the language of the law courts in the West, and of the military everywhere. After all freeborn inhabitants of the Empire were universally enfranchised in 212 AD, a great number of Roman citizens would have lacked Latin, though they were expected to acquire at least a token knowledge, and Latin remained a marker of "Romanness".

Koine Greek had become a shared language around the eastern Mediterranean and into Asia Minor as a consequence of the conquests of Alexander the Great. The "linguistic frontier" dividing the Latin West and the Greek East passed through the Balkan peninsula. Educated Romans, particularly those of the ruling elite, studied and often achieved a high degree of fluency in Greek, which was useful for diplomatic communications in the East even beyond the borders of the Empire. The international use of Greek was one condition that enabled the spread of Christianity, as indicated for example by the choice of Greek as the language of the Epistles of Paul and its use for the ecumenical councils of the Christian Roman Empire. With the dissolution of the Empire in the West, Greek became the dominant language of the Eastern Roman Empire, later known as the Byzantine Empire.

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