(BA) Eastern Roman Empire

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The Roman Empire, spreading from Rome, naturally used Latin as its language of administration. As it began to conquer various areas east of Rome, areas that had been Hellenized, those areas continued to use Greek as their lingua franca. Starting in 286, with some interruptions afterward, administration of the Roman Empire was split into two, into East and West, both functioning somewhat separately as halves of a single empire.

In 330, Constantine, the first Christian Emperor, moved the capital of the Roman Empire to the newly built city of Constantinople, which would from then on be a major power center, religious and political. By 476 the Western Roman Empire had fallen, while the East survived until 1453. The Eastern Roman Empire, after the fall of the West, is typically referred to by modern writers as the "Byzantine Empire". It is by means of this redefinition that one can take the view that the Roman Empire fell at the beginning, rather than end, of the medieval period.

The Church within the Western Roman Empire, using Latin and based in Rome, would become the Roman Catholic Church. Its language of Latin would evolve into Portuguese, Spanish, French, and Italian.

The Church within the Eastern Roman Empire would become Eastern Orthodoxy, with its power center -- to the extent that it had such a thing -- in Constantinope. This Church used Greek as its primary language.

The Eastern Roman Empire fell in 1453, about the time that the printing press was invented (about 1439). As printing presses spread, so did literacy and widespread reading of books, fueling the Protestant Reformation, beginning in about 1517 with Martin Luther -- though of course Protestantism has prior antecendants. This Reformation would find its way back toward the East under Cyril Lucarius, patriarch of Constantinople who -- it has been said -- was a Calvinist.

The post-Byzantine Church was not to become Calvinist, however, as Cyril Lucaris was murdered in 1638. I don't think we can know what direction things might have taken had he died. Cyril Lucaris had brought the first printing press to Constantinople in 1627.