Emperor (or Empress)	Dates of Reign
Constantine I (the Great)	330-37
Constantius	337-61
Julian (the Apostate)	361-63
Jovian	363-64
Valens	364-78
Theodosius I (the Great)	379-95
Arcadius	395-408
Theodosius II	408-50
Marcian	450-57
Leo I (the Great or the Thracian)	457-74
Leo II	474
Zeno	474-75
Basiliscus	475-76
Zeno (restored)	476-91
Anastasius I	491-518
Justin I	518-27
Justinian I (the Great)	527-65
Justin II	565-78
Tiberius II Constantinus	578-82
Maurice	582-602
Phocas	602-10
Heraclius	610-41
Constantine III and Heracleonas	641
Heracleonas	641
Constans II Pogonatus	641-68
Constantine IV	668-85
Justinian II Rhinotmetus	685-95
Leontius	695-98
Tiberius III	698-705
Justinian II (restored)	705-11
Philippicus Bardanes	711-13
Anastasius II	713-15
Theodosius III	716-17
Leo III (the Isaurian or the Syrian)	717-41
Constantine V Copronymus	741-75
Leo IV (the Khazar)	775-80
Constantine VI	780-97
Irene	797-802
Nicephorus I	802-11
Stauracius	811
Michael I	811-13
Leo V (the Armenian)	813-20
Michael II (the Stammerer)	820-29
Theophilus	829-42
Michael III (the Drunkard)	842-67
Basil I (the Macedonian)	867-86
Leo VI (the Wise or the Philosopher)	886-912
Alexander	912-13
Constantine VII Porphyrogenitus	913-19
Romanus I Lecapenus	919-44
Constantine VII (restored)	944-59
Romanus II	959-63
Basil II Bulgaroktonos	963
Nicephorus II Phocas	963-69
John I Tzimisces	969-76
Basil II (restored)	976-1025
Constantine VIII	1025-28
Zoë and Romanus III Argyrus	1028-34
Zoë and Michael IV (the Paphlagonian)	1034-41
Zoë and Michael V Calaphates	1041-42
Zoë and Theodora	1042
Zoë, Theodora, and Constantine IX Monomachus	1042-50
Theodora and Constantine IX	1050-55
Theodora	1055-56
Michael VI Stratioticus	1056-57
Isaac I Comnenus	1057-59
Constantine X Ducas	1059-67
Michael VII Ducas (Parapinaces)	1067-68
Romanus IV Diogenes	1068-71
Michael VII Ducas (restored)	1071-78
Nicephorus III Botaniates	1078-81
Alexius I Comnenus	1081-1118
John II Comnenus	1118-43
Manuel I Comnenus	1143-80
Alexius II Comnenus	1180-83
Andronicus I Comnenus	1183-85
Isaac II Angelus	1185-95
Alexius III Angelus	1195-1203
Isaac II (restored) and Alexius IV Angelus	1203-4
Alexius V Ducas	1204
Theodore I Lascaris	1204-22
John III Vatatzes or Ducas	1222-54
Theodore II Lascaris	1254-58
John IV Lascaris	1258-61
Michael VIII Palaeologus	1259-82
Andronicus II Palaeologus	1282-1328
Andronicus III Palaeologus	1328-41
John V Palaeologus	1341-76
John VI Cantacuzenus (usurper)	1347-55
Andronicus IV Palaeologus	1376-79
John V Palaeologus (restored)	1379-91
John VII Palaeologus (usurper)	1390
Manuel II Palaeologus	1391-1425
John VII Palaeologus (restored as coemperor)	1399-1412
John VIII Palaeologus	1425-48
Constantine XI Palaeologus	1449-53

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 (A.D. 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.

Early Centuries

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.

Empire, southeastern and southern Europe and western Asia. It began as the city of Byzantium, which had grown from an ancient Greek colony founded on the European side of the Bosporus. The city was taken in AD 330 by Constantine I, who refounded it as Constantinople. The area at this time was generally termed the Eastern Roman Empire. The fall of Rome in 476 ended the western half of the Roman Empire; the eastern half continued as the Byzantine Empire, with Constantinople as its capital. The eastern realm differed from the west in many respects: heir to the civilization of the Hellenistic era, it was more commercial and more urban. Its greatest emperor, Justinian (r. 527–565), reconquered some of western Europe, built the Hagia Sophia, and issued the basic codification of Roman law. After his death the empire weakened. Though its rulers continued to style themselves “Roman” long after Justinian's death, “Byzantine” more accurately describes the medieval empire. The long controversy over iconoclasm within the eastern church prepared it for the break with the Roman church (see Schism of 1054). During the controversy, Arabs and Seljuq Turks increased their power in the area. In the late 11th century, Alexius I Comnenus sought help from Venice and the pope; these allies turned the ensuing Crusades into plundering expeditions. In the Fourth Crusade the Venetians took over Constantinople and established a line of Latin emperors. Recaptured by Byzantine exiles in 1261, the empire was now little more than a large city-state. In the 14th century the Ottoman Turks began to encroach; their extended siege of Constantinople ended in 1453, when the last emperor died fighting on the city walls and the area came under Ottoman control.

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