Greek East and Latin West

"Greek East" and "Latin West" are terms used to distinguish between the two parts of the Greco-Roman world, specifically the eastern regions where Greek was the lingua franca, and the western parts where Latin filled this role. During the Roman Empire a divide had persisted between Latin- and Greek-speaking areas; this divide was encouraged by administrative changes in the empire's structure between the 3rd and 5th centuries, which led ultimately to the establishment of separate Eastern and Western halves of the Empire.

After the fall of the Western Empire, the terms "Greek East" and "Latin West" are applied to areas that were formerly part of the Eastern or Western Empires, and also to areas that fell under the Greek or Latin cultural sphere but that had never been part of the Roman Empire. In this sense, particular attention is given to differences in Christianity in the two parts, specifically between Western Christianity and Eastern Christianity.

In the classical context, "Greek East" refers to the provinces and client states of the Roman Empire in which the lingua franca was primarily Greek.

This region included the whole Greek peninsula with some other northern parts in the Balkans, the provinces around the Black Sea, those of the Bosphorus, all of Asia Minor (in the loosest possible sense, to include Cappadocia and extending to Armenia Minor), Magna Graecia (southern part of the Italian peninsula and Sicily), and the other provinces along the eastern rim of the Mediterranean Sea (Judea, Syria, Cyrenaica and Egypt). These Roman provinces had been Greek colonies or Greek-ruled states during the Hellenistic period, i.e. until the Roman conquests.

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