Byzantium, also known as the Eastern Roman Empire, was a state formed during the collapse of the Roman Empire in its eastern part (namely, the Balkan Peninsula, Asia Minor, and the south-eastern Mediterranean) and existed from the 4th to the 15th centuries.
Its capital was Constantinople. The official languages at various times were Middle Greek and Latin.
Byzantium reached its greatest territorial expansion in the 6th century under Justinian I.
The fall of Constantinople in 1453 and its conquest by the Turks put an end to the Byzantine Empire.
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