Byzantine Empire, successor state to the Roman Empire (see under Rome), also called Eastern Empire and East Roman Empire. It was named after Byzantium, which Emperor Constantine I rebuilt (AD 330) as Constantinople and made the capital of the entire Roman Empire. Although not foreseen at the time, a division into Eastern and Western empires became permanent after the accession (395) of Honorius in the West and Arcadius in the East.
Throughout its existence the Byzantine Empire was subject to important changes in its boundaries. The core of the empire consisted of the Balkan Peninsula (i.e., Thrace, Macedonia, Epirus, Greece proper, the Greek isles, and Illyria) and of Asia Minor (present-day Turkey). The empire combined Roman political tradition, Hellenic culture, and Christian beliefs. Greek was the prevalent language, but Latin long continued in official use.
See the table entitled Rulers of the Byzantine Empire for a list of all the Byzantine emperors and the years they reigned.
The characteristic Eastern influence began with Constantine I, who also introduced Christianity. Orthodoxy triumphed over Arianism under Arcadius' predecessor, Theodosius I, but violent religious controversy was chronic. The reigns (395–527) of Arcadius, Theodosius II, Marcian, Leo I, Leo II, Zeno, Anastasius I, and Justin I were marked by the invasions of the Visigoths under Alaric I, of the Huns of Attila, and of the Avars, the Slavs, the Bulgars (see Bulgaria), and the Persians. After the Western Empire fell (476) to Odoacer, Italy, Gaul, and Spain were theoretically united under Zeno but were actually dominated by, respectively, the Ostrogoths, the Franks, and the Visigoths, while Africa was under the Vandals. During this period arose the heresies of Nestorianism and Monophysitism and the political parties of Blues and Greens to divide the Byzantines.
Revival and Hellenization
Under the rule (527–65) of Justinian I and Theodora, Byzantine power grew. Their great generals, Belisarius and Narses, checked the Persians, repressed political factions, and recovered Italy and Africa, while Tribonian helped the emperor to codify Roman law. During Justinian's reign a great revival of Hellenism took place in literature, and Byzantine art and architecture entered their most glorious period.
Much was lost again under his successors. The Lombards conquered most of Italy; however, the Pentapolis (Rimini, Ancona, Fano, Pesaro, and Senigallia), Rome, Sardinia, Corsica, Liguria, and the coasts of S Italy and Sicily long remained under Byzantine rule, and at Ravenna the exarchs governed until 751. The Persians, under Khosrow I, made great gains against the empire, though Emperor Maurice temporarily checked them in 591.
The emperor Heraclius (610–41) defeated the Persians but was barely able to save Constantinople from the Avars. Muslim conquests soon afterward wrested Syria, Palestine, Egypt, Africa, and Sicily from the empire. Heraclius's attempt to reconcile Monophysitism and orthodoxy merely led to the new heresy of Monotheletism. His military reorganization of the provinces into themes proved effective and was continued by Constans II (641–48). Constantine IV (668–85) saved Constantinople from Arab attack.
The 7th cent. was marked by increasing Hellenization of the empire, outwardly symbolized by the adoption of the Greek title Basileus by the emperors. The church, under the patriarch of Constantinople, became increasingly important in public affairs. Theology, cultivated by emperors and monks alike, was pushed to extremes of subtlety. Literature and art became chiefly religious.
Under Justinian II and his successors the empire was again menaced by Arabs and Bulgars, but the Isaurian emperors Leo III (717–41) and Constantine V stopped the Arab advance and recovered Asia Minor. The grave issue of iconoclasm, which they precipitated, led to the loss of Rome. In 800, during the reign of Irene, the Frank Charlemagne was crowned emperor of the West at Rome. Thus ended even the theoretical primacy of Byzantium over Europe.
A Truly Eastern State
The political division of East and West was paralleled by a religious schism, intensified by the patriarch Photius, between the Roman and the Orthodox Eastern Church, later culminating in a complete break (1054). In all aspects the Byzantine Empire, having lost its claim to universality, became a Greek monarchy, though Constantinople still remained the center of both Greek and Roman civilization. Compared with its intellectuals, artists, writers, and artisans, those of Western Europe were crude and barbarous, though sometimes more vigorous and original.
In the empire the administrative machinery was huge, and competition among the courtiers was intense. Complex diplomacy, intrigue, and gross violence marked the course of events; yet moral decay did not prevent such emperors as Basil I, founder of the Macedonian dynasty, and his successors (notably Leo VI, Romanus I, Constantine VII, Nicephorus II, John I, and Basil II) from giving the empire a period of splendor and power (867–1025). The eastern frontier was pushed to the Euphrates River, the Bulgars were subjugated, and the Balkan Peninsula was recovered. Russia, converted to Christianity, became an outpost of Byzantine culture. In the unceasing struggle between the great landowners and the small peasantry, most of the emperors favored the peasants. Economic prosperity was paralleled by a new golden age in science, philosophy, and architecture.
The Ebb of Power
With the rule of Zoë (1028–50) anarchy and decline set in. The Seljuk Turks increased their attacks, and with the defeat (1071) of Romanus IV at Manzikert most of Asia Minor was permanently lost. The Normans under Robert Guiscard and Bohemond I seized S Italy and attacked the Balkans. Venice ruled the Adriatic and challenged Byzantine commercial dominance in the East, and the Bulgars and Serbs reasserted their independence.
Alexius I (1081–1118) took advantage of the First Crusade (see Crusades) to recover some territory in Asia Minor and to restore Byzantine prestige, but his successors of the Comnenus dynasty were at best able to postpone the disintegration of the empire. After the death (1180) of Manuel I the Angelus dynasty unwittingly precipitated the cataclysm of the Fourth Crusade. In 1204 the Crusaders and the Venetians sacked Constantinople and set up a new empire (see Constantinople, Latin Empire of) in Thrace, Macedonia, and Greece. The remainder of the empire broke into independent states, notably the empires of Nicaea and of Trebizond and the despotate of Epirus.
In 1261 the Nicaean emperor Michael VIII conquered most of the tottering Latin empire and reestablished the Byzantine Empire under the Palaeologus family (1261–1453). The reconstructed empire was soon attacked from all sides, notably by Charles I of Naples, by Venice, by the Ottoman Turks, by the new kingdoms of Serbia and Bulgaria, and by Catalonian adventurers under Roger de Flor. At the same time, the empire began to break down from within—the capital was at odds with the provinces; ambitious magnates were greedy for land and privileges; religious orders fought each other vigorously; and church and state were rivals for power.
Eventually the Turks encircled the empire and reduced it to Constantinople and its environs. Manuel II and John VIII vainly asked the West for aid, and, in 1453, Constantinople fell to Sultan Muhammad II after a final desperate defense under Constantine XI. This is one of the dates conventionally accepted as the beginning of the modern age. The collapse of the empire opened the way for the vast expansion of the Ottoman Empire to Vienna itself and also enabled Ivan III of Russia, son-in-law of Constantine XI, to claim a theoretical succession to the imperial title.
The classic, though biased, work on Byzantine history is Gibbon's Decline and Fall of the Roman Empire. More recent standard works are those of J. B. Bury, C. Diehl, A. A. Vasil'ev, G. Ostrogorsky, and N. H. Baynes. See also studies by J. M. Hussey (1967, 1986), R. J. H. Jenkins (1967), D. Obolensky (1971), S. Runciman (1971, 1977), M. Angold (1985), J. Herrin (1987, 2008), J. J. Norwich (1995), and E. N. Luttwak (2009).