The Byzantine Empire (Koine Greek: Βασιλεία Ῥωμαίων), also known as the Eastern Roman Empire, was the continuation of the Roman Empire in its eastern provinces.
It lasted from the 5th century AD until its fall to the Ottoman Empire in 1453. It was a powerful economic, cultural, and military force in the Mediterranean, with its capital in Constantinople (modern-day Istanbul, Turkey). While its citizens identified themselves Romans, it is distinct from the earlier Roman Empire due to factors like the shift of the capital, the integration of Christianity, and the use of Greek instead of Latin.
Over its history, the Byzantine Empire went through periods of expansion and decline. It reached its peak under Emperor Justinian I, reconquering previous western Mediterranean territories. It faced challenges from conflicts, including the Byzantine-Sasanian Wars and Muslim conquests, which led to the loss of key provinces. The Macedonian dynasty oversaw a revival, but it eventually declined due to civil wars and the Fourth Crusade, which divided its territories.
Making a brief recovery in 1261, the Byzantine Empire remained a regional power until its fall in 1453. The Fall of Constantinople marked the end of the empire and the start of the early modern period. Refugees from Constantinople played a role in the Renaissance, and the fall of the Empire of Trebizond followed shortly after.
Its existence has a lasting legacy, particularly in the fields of art, architecture, law, and Christianity, which continue to influence the world to this day.