Byzantine Empire

Introduction & Top Questions
The empire to 867
- The Roman and Christian background
  - Unity and diversity in the late Roman Empire
  - The reforms of Diocletian and Constantine
- The 5th century: Persistence of Greco-Roman civilization in the East
  - Economic and social policies
  - Relations with the barbarians
  - Christological controversies
  - The empire at the end of the 5th century
- The 6th century: from East Rome to Byzantium
  - The years of achievement to 540
  - The crisis of mid-century
  - The last years of Justinian I
  - Christian culture of the Byzantine Empire
  - The successors of Justinian: 565–610
- The 7th century: the Heraclians and the challenge of Islam
  - Heraclius and the origin of the themes
  - The successors of Heraclius: Islam and the Bulgars
- The age of Iconoclasm: 717–867
  - The reigns of Leo III (the Isaurian) and Constantine V
  - Constantine’s weak successors
  - The Iconoclastic controversy
From 867 to the Ottoman conquest
- The Macedonian era: 867–1025
  - Military revival
  - Relations with the Slavs and Bulgars
    - Bulgarian wars
    - Relations with Russia
    - Bulgar revolt
  - Estrangement from the West
  - Culture and administration
  - Social and economic change
- Byzantine decline and subjection to Western influences: 1025–1260
  - 11th-century weakness
  - Arrival of new enemies
  - Alexius I and the First Crusade
  - Later Comneni
  - The Fourth Crusade and the establishment of the Latin Empire
- The empire under the Palaeologi: 1261–1453
  - Michael VIII
  - Andronicus II
  - Cultural revival
  - Andronicus III and John Cantacuzenus
  - Turkish expansion
  - Manuel II and respite from the Turks
  - Final Turkish assault
Byzantine emperors

References & Edit History Quick Facts & Related Topics

Images

Map showing the changing boundaries of the Byzantine Empire around the eastern Mediterranean. Three areas are marked: the largest outline shows the empire's greatest extent under Justinian I (527-565), a medium pink area shows the empire in about 1020, and a smaller red area shows the empire in about 1360. Key regions include Asia Minor, Greece, the Balkans, and parts of Italy, North Africa, and the eastern Mediterranean coast, with Constantinople marked as the capital.

Red porphyry statue group of four Roman emperors, known as the Tetrarchs, standing in pairs and embracing, set against a marble wall in Venice.

At a Glance

Byzantine Empire summary

Byzantine Empire

historical empire, Eurasia

Also known as: Byzantium, East Rome, Eastern Roman Empire

Written by

John L. TeallAll

Fact-checked by

Britannica Editors

Last updated

Nov. 12, 2026 •History

Byzantine Empire, the eastern half of the Roman Empire, which survived for a thousand years after the western half had crumbled into various feudal kingdoms and which finally fell to Ottoman Turkish onslaughts in 1453. The very name Byzantine illustrates the misconceptions to which the empire’s history has often been subject, for its inhabitants would hardly have considered the term appropriate to themselves or to their state. Theirs was, in their view, none other than...

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