History › Classical age › Roman Empire
Byzantine Empire
330 (Constantinople founded) – 1453· Empire, kingdom or state· Europe
Well documentedSolid records, physical evidence or scientific consensus.
The eastern, Greek-speaking half of the Roman Empire, ruled from Constantinople for over a thousand years after the West fell.
See it on the History map →What happened
Its people called themselves Romans; 'Byzantine' is a label coined by later scholars from Byzantium, Constantinople's old name. Emperor Justinian (527–565) reconquered Italy and North Africa, codified Roman law and built the Hagia Sophia. Arab conquests in the 600s took Syria and Egypt. Its Orthodox church split from Rome's in 1054. Crusaders sacked the capital in 1204, and the Ottomans captured it in 1453, ending the empire.
Why it matters
It preserved Roman law and Greek learning, shielded Europe from eastern invasions for centuries, and spread Orthodox Christianity and the Cyrillic alphabet to Russia and the Balkans.
How we know
Justinian's law code, histories by Procopius and the princess Anna Komnene, surviving churches and mosaics, coins, and Western and Arab accounts.
Still debated
When 'Roman' becomes 'Byzantine' is a matter of convention: historians variously pick 330, 395, 476 or the 600s.
Connections (5)
▸Constantine the Great founded the capital of Byzantine EmpireWell documented
The connection
Constantine rebuilt the old Greek town of Byzantium on the Bosporus strait as a 'New Rome', dedicating it in 330. Controlling the sea route between the Black Sea and the Mediterranean, and close to the rich eastern provinces and frontiers, it became the capital of the eastern empire for over 1,100 years. It is today's Istanbul.
When and how
Byzantium, on the Bosporus, 324–330; Constantine.
How we know
Contemporary writers, surviving monuments such as the Column of Constantine, and the name itself: Constantinople, 'Constantine's city'.
Debates and open questions
Whether he planned a Christian capital or a traditional Roman one is debated; the city also displayed many pagan statues.
▸Byzantine Empire ended with the Fall of ConstantinopleWell documented
The connection
The eastern Roman Empire, called Byzantine by later historians, had shrunk for centuries: the Fourth Crusade sacked Constantinople in 1204, and by 1450 it held little more than the city and parts of Greece. When the Ottomans took the city in 1453, the last emperor, Constantine XI, died in the fighting, ending a state that traced back to Augustus.
When and how
Constantinople, April 6–May 29, 1453; Emperor Constantine XI Palaiologos against Sultan Mehmed II. The last Byzantine Greek states, the Morea and Trebizond, fell by 1461.
How we know
Byzantine, Italian and Ottoman eyewitness accounts agree on the city's capture and the emperor's death, though not on how he died.
Debates and open questions
How Constantine XI died, and whether more Western help could have saved the city, are debated.
▸Byzantine Empire lost Syria and Egypt to Islamic caliphatesWell documented
The connection
Exhausted by a long war with Persia (602–628), the Byzantine Empire could not stop the new Arab Muslim armies. After defeat at the Yarmuk River in 636, it lost Syria and Palestine, and then Egypt, its richest province and breadbasket. Caliphate forces later besieged Constantinople itself, in 674–678 and 717–718, but failed.
When and how
The Yarmuk River, near today's Syria–Jordan border, 636; Jerusalem surrendered in 637; Alexandria fell by 641–642.
How we know
Byzantine chronicles like that of Theophanes; Arabic conquest histories; Egyptian papyri showing a fairly smooth change of tax collectors.
Debates and open questions
How much local Christians resisted, welcomed or simply tolerated the new rulers is debated; many were at odds with Constantinople over doctrine.
▸Byzantine Empire asked for help, triggering The CrusadesWell documented
The connection
After the Seljuk Turks defeated Byzantium at Manzikert in 1071 and overran most of Anatolia, Emperor Alexios I Komnenos asked Pope Urban II for western soldiers. The pope turned the request into a far bigger call to free Jerusalem. Crusaders later turned on Byzantium itself, sacking Constantinople in 1204.
When and how
The Council of Piacenza, Italy, March 1095, where Byzantine envoys appealed; Urban's sermon at Clermont, France, November 1095.
How we know
Western chronicles of Piacenza; the Alexiad, a history by Alexios's daughter Anna Komnene describing the crusaders' arrival.
Debates and open questions
Alexios probably wanted mercenaries under his command, not independent armies; how much his appeal shaped the pope's call is debated.
▸Fall of the Western Roman Empire left standing, as Rome's surviving half, the Byzantine EmpireMostly agreed
The connection
From 395 the empire was split between two courts. The East was richer, more urban and protected by Constantinople's walls, so it rode out the 400s' invasions. When the West collapsed in 476, the eastern emperor became the only Roman emperor. Justinian later reconquered Italy and North Africa, but those gains proved short-lived.
When and how
Constantinople and the western provinces, 395–565; Odoacer, Emperor Zeno and, later, Justinian.
How sure are we?
Contemporary chronicles report that Odoacer sent the western imperial regalia to Constantinople, accepting Zeno as sole emperor.
Debates and open questions
Why the East survived when the West did not (wealth, geography, walls or luck) is debated.