The Byzantine Empire, also referred to as the Eastern Roman Empire, was the continuation of the Roman Empire centered in Constantinople during Late Antiquity and the Middle Ages. The eastern half of the Empire survived the conditions that caused the fall of the West in the 5th century AD, and continued to exist until the fall of Constantinople to the Ottoman Empire in 1453. During most of its existence, the empire remained the most powerful economic, cultural, and military force in the Mediterranean world. The term "Byzantine Empire" was only coined following the empire's demise; its citizens referred to the polity as the "Roman Empire" and to themselves as "Romans". Due to the imperial seat's move from Rome to Byzantium, the adoption of state Christianity, and the predominance of Greek instead of Latin, modern historians continue to make a distinction between the earlier Roman Empire and the later Byzantine Empire.
Gold solidus of Leo III (left), and his son and heir, Constantine V (right)
Constantinople was the largest and wealthiest city in Europe throughout late antiquity and most of the Middle Ages until the Fourth Crusade in 1204.
The seizure of Edessa (1031) by the Byzantines under George Maniakes and the counterattack by the Seljuk Turks
Alexios I, founder of the Komnenos dynasty
The Roman Empire was the post-Republican state of ancient Rome. It is generally understood to mean the period and territory ruled by the Romans following Octavian's assumption of sole rule under the Principate in 27 BC. It included territories in Europe, North Africa, and Western Asia and was ruled by emperors. The fall of the Western Roman Empire in 476 AD conventionally marks the end of classical antiquity and the beginning of the Middle Ages.
Augustus of Prima Porta
Nerva (r. 96–98)
Trajan (r. 98–117)
Hadrian (r. 117–138)