The Byzantine Empire, also known as the Eastern Roman Empire, was a continuation of the Roman Empire in the east. It was centered in Constantinople (present-day Istanbul) and lasted from 330 AD to 1453 AD. The Byzantine Empire was a major power in the Mediterranean and Middle East for over a thousand years. It played a key role in the spread of Christianity and the development of Western civilization. The Byzantine Empire was eventually conquered by the Ottoman Turks in 1453 AD.
Sassanid Empire
The Sassanid Empire was a powerful Persian dynasty that ruled over much of the Middle East from 224 AD to 651 AD. The Sassanians were a major rival of the Byzantine Empire. They fought a series of wars with the Byzantines over control of territories in the Middle East and North Africa. The Sassanid Empire was eventually defeated by the Arab Muslims in 651 AD.