The Turkish emir Osman I, father of the Ottoman dynasty, had a dream. A tree sprang from his loins, and from its roots flowed the great rivers of the world, and its canopy spread from the Caucasus to the Atlas. In the branches nightingales and parrots cried out. Every leaf was a scimitar. A wind blew up that turned these blades toward the cities that lay beneath the tree; most turned toward Constantinople. That city became the emerald in a ring, and the emir slipped the ring on his finger, and awoke.

The Byzantines had said that when, as at its founding in A.D. 330, they were again ruled by an emperor named Constantine, son of a Helena, Constantinople would fall, which in 1453 they were and it did.

The Muslims foretold that a leader who bore the Prophet’s name would take Constantinople, and in 1453 he did and he did.

When the Turks at last breached Constantinople’s walls it was because someone left the door open. At the moment they entered the great church of Hagia Sophia, the priest conducting the mass disappeared into the walls. They found a golden door high in the wall but their masons could not open it.

No witness was found to the death of Constantine XI Dragases Palaeologus, and it is not possible to say with certainty how he died that day or by whose hand or even whether he died at all.

What was Byzantium? The Hellenic east of the Roman Empire had been first provincial holdings and then, with the imperium split between West and East, an equal and conjoined power, and then, with the diminishment of the West, became Rome itself, refulgent.

What were its borders, the appearances of its cities? At greatest extent Byzantium comprised Turkey, Egypt, North Africa, Macedonia, Bulgaria, the Levant, the Sinai, Greece, Illyria, and (when the emperor Justinian I briefly retook the West) Italy and Sicily and Corsica and Andalusia. Pagan classicism—marmoreal, monumental, certain of the primacy of earthly life—yielded to Christian abstraction and introspection. Art was now the ornament and not the celebration of a transitory world; the physical would never again be heroic. And yet what, wondered Bishop Porphyry of Gaza, might Heaven hold if this city of Constantinople could be so grand?

Halfway between Heaven and earth were tollbooths where demons taxed the sins of the Byzantines. Byzantium was efficient in Christ, sophisticated, cautious; a splendor enameled and golden. Its minds were hyaline and humorless. The world was twice as long as it was wide. There was no purgatory.

In 628 the emperor Heraclius summoned Mohammed’s cousin Abu Sufyaan, messenger of the messenger of God, and put to him many questions by which he hoped to weigh the authority of the Prophet. He asked: “Has any among your people ever claimed to be a prophet before him?” He was told: “No.” He asked: “Was any among his ancestors a king?” He was told: “No.” He asked: “Is it the noble among the people or the weak who follow him?” He was told: “The weak.” He asked: “Are his followers increasing or decreasing in number?” He was told: “They are increasing.” He asked: “Does he break his promises?” He was told: “No.” Heraclius concluded: “Verily, if what you say is true, he will rule the ground beneath my feet.”

“Verily you shall conquer Constantinople,” Mohammed promised his followers. “But the Byzantines with horns are people of sea and rock; whenever a horn goes, another replaces it. Alas, they are your associates to the end of time.”

The Byzantines called themselves Greeks (because they were) and also Romans (because they had been). To the Muslims, who had been the Arabs (who had coveted Constantinople even before they were Muslims) but were later the Turks, the Byzantines were usually the Romans (Rum) and sometimes, though these Romans spoke Greek, the Latins (which to the Byzantines meant the barbarians of Western Europe), and sometimes the Children of the Yellow One, who was Esau. The Arabs called the Byzantine emperor (who signed his letters in purple ink EMPEROR AND AUTOCRAT OF THE ROMANS) the Dog of the Byzantines, and by the fifteenth century the sultan of the Ottoman Turks (whom the Muslims farther east called Romans and whom the Byzantines called Trojans) called himself sultan i-Rum in expectation that he soon would be and in recognition that he already, for most purposes, was.

In 912, Harun ibn Yahya was taken prisoner by the Byzantines and brought to Constantinople, where he witnessed the emperor in procession from the palace to the great church, followed by fifty-five thousand two hundred and twelve young Khazars and Turks in stripes and middle-aged eunuchs in white and men and youths and boys and servants and patricians in brocade, and “In his hand is a golden box containing dust. He goes on foot. Every two steps he stops, and his minister says the words ‘Remember death,’ and he stops to open the box, look at the dust, kiss it, and weep.”

What were the laws and practices of the lawgivers? The Great Code of Theodosius forbade the impersonation of nuns by female mimes and the trampling of Jews by gentiles; the edicts of Leo VI permitted eunuchs to adopt; the Orthodox patriarchs anathematized the Manichaeans’ belief that all things fermented are alive.

The rulers of Byzantium were accustomed to blinding their rivals. With ornamental eye scoops, with daggers, with candelabras, kitchen knives, and tent pegs, with burning coals and boiling vinegar, with red-hot bowls held near the face and with bandages that left the eyes unharmed but were forbidden to be removed; sometimes it was sufficient merely to singe the eyelashes, for the victim to bellow and sigh like a lion as a trained executioner pantomimed the act. Sometimes cruelty was intended beyond the enucleation itself, as when the emperor Diogenes Romanus was deposed and “they permitted some unpracticed Jew to proceed in blinding the eyes” and “he lived several days in pain and exuding a bad odor.” In 797 the empress regnant Irene blinded her son Constantine VI and caused an eclipse that lasted seventeen days. Basil II blinded fifteen thousand Bulgarian soldiers, and every hundredth man he left with one eye to lead another ninety-nine, and when these men returned home to their king Samuel he looked upon them and died. Michael V blinded his uncle John the Master of Orphans. The iconoclasts blinded the eyes of the icons.

It was said that the city would fall when ships sailed by over dry land.

Constantinople had a thousand churches and insuperable walls landward and seaward. On the main approach to the palace, only the perfume merchants were permitted their trade. In the imperial throne room was a golden tree in whose branches mechanical birds sang and beside which mechanical lions roared. On a fine cushion next to the levitating Throne of Solomon sat a green goose who screamed if the emperor’s meals were poisoned. The emperor alone could pass back and forth through the membrane separating his court from God’s.

Envoys from the Chinese court reported that “there are jugglers who can let fires burn on their foreheads; make rivers and lakes in their hands; raise their feet and let pearls and precious stones drop from them; and, in opening their mouths produce banners and tufts of feathers in abundance”; that there were jade-colored pearls which coagulated in the saliva of flying birds, lambs who sprouted from the ground and had to be startled into breaking their umbilical cords, and dwarves who worked the fields in fear of being eaten by cranes.

The Byzantines sent to the Fatimid court white peacocks, white ravens, and large bears who played music. They performed divination by thunder, lightning, and the moon.

The emperor Leo the Wise prophesied the doom of Constantinople. (The dreams of man may come from God, accorded the science of the Muslims, but they may come also from the Devil, or from man himself.) Leo created a toad, or a marble tortoise, who roamed the streets at night and consumed all the city’s refuse. He built a bathhouse for the poor that was destroyed by its guardian sagittary statue when the bathkeepers began to charge admission.

The emperor Alexius I built within Constantinople a separate city for wretches. The poor were ephemeral, unsurvived by new generations: different persons grew poor and replaced them.

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