Byzantium: the Roman empire in the east

The Roman empire did not end in 476. Its eastern half, ruled from Constantinople, lasted until 29 May 1453.

A Roman empire that spoke Greek

“Byzantine” is a modern label taken from Byzantium, the old Greek name of the city that Constantine rebuilt as Constantinople and dedicated in 330. The people we call Byzantines called themselves Romans, Rhomaioi in Greek, and their ruler was the Roman emperor. Latin stayed the language of law and the army for a while, but Greek was the everyday language of the east, and by the 7th century it was the language of government too. The city stood on a point of land between the Black Sea and the Mediterranean, with water on three sides and the Golden Horn as a sheltered harbour. On the land side, the Theodosian Walls of the early 5th century, two lines of walls with a moat in front, held off attackers for a thousand years.

Justinian and Theodora

The emperor Justinian I, who reigned from 527 to 565, set out to win back the western provinces. His general Belisarius took North Africa from the Vandals in 533 and 534, and after a long and ruinous war Italy was recovered from the Ostrogoths. At home, Justinian ordered a commission of lawyers to collect and tidy centuries of Roman law. The result, later called the Corpus Juris Civilis (Body of Civil Law), became one of the foundations of law in much of Europe. In January 532 rival chariot-racing fans joined in a riot known as the Nika revolt and burned much of the city centre. Procopius, the court historian, says that Justinian was ready to flee until the empress Theodora told the council she would rather die an empress than live as a fugitive. The revolt was crushed with great bloodshed. In 541 and 542 plague swept the empire, the first well documented outbreak of the disease caused by Yersinia pestis, the same bacterium as the Black Death of unit 7.

Hagia Sophia

Among the buildings lost in the riot was the cathedral, Hagia Sophia, “Holy Wisdom”. Justinian had it rebuilt from 532 to 537 by two men trained in geometry and mechanics, Anthemius of Tralles and Isidore of Miletus. The Met calls them among the few Byzantine architects whose names are recorded. Their design set a dome about 31 metres across over a square space, carried on four curved triangles of masonry called pendentives. A ring of 40 windows at its base makes the dome seem to float, and Procopius wrote that it looked as if it hung from heaven on a golden chain. An earthquake brought part of the dome down in 558; it was rebuilt with a taller profile by 562. After 1453 Hagia Sophia became a mosque, in 1935 a museum, and in 2020 a mosque again.

Fire on the water and a long decline

Byzantium survived wave after wave of attack. Arab armies besieged Constantinople in the 670s and again in 717 and 718. The defenders used Greek fire, a liquid that kept burning on water and was sprayed from tubes mounted on ships; its recipe is still unknown. Inside the empire a long quarrel called iconoclasm, “image breaking”, split the church from the 720s until 843 over whether holy images could be honoured. Relations with the Latin church in Rome grew colder, and in 1054 the pope’s envoys and the patriarch of Constantinople excommunicated each other, a break later called the Great Schism. After a defeat by the Seljuk Turks at Manzikert in 1071 the emperors lost much of Anatolia, and in 1204 the army of the Fourth Crusade sacked Constantinople itself (unit 5). The Byzantines took their city back in 1261, but the empire never regained its strength.