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10. Siege of Constantinople |

Siege of Constantinople is drawn from Chapter Ten, beginning on page 255, of Volume Five, The Sword of Islam of the twelve-volume historical series The Christians: Their First Two Thousand Years. If you would like to order this book please visit

A great Muslim armada blockades the Byzantine capital, but Christian determination and a deadly secret weapon decide one of the most pivotal events in western history

Siegel of Constantinople - Islam’s final goal, the glittering prize of Constantinople

Siegel of Constantinople - Islam’s final goal, the glittering prize of Constantinople
The fabled city of Constantinople, from a medieval German woodcut. By 717, much of the Christian world had been lost to Islam, and the Muslim juggernaut once more turned its attention to the imperial capital. Its fall appeared imminent, a foregone conclusion.

To the Muslims in the ninety-seventh year of hijra (the Christian year 717), the war to conquer the world for Islam was all but won. The vast and ostensibly omnipotent Persian Empire had by now been Islamic for eighty years. Syria was Muslim, as was the government of Egypt. In North Africa, the cries of the muezzin sounded from mosques that had once been churches, and the Berbers were learning to memorize the Qur’an rather than listen to the Bible. The Mediterranean could now be considered a Muslim sea. Muslim troops were hard at work on the conquest of Sicily. Italian ports were under attack, and it seemed certain that southern Italy would be engulfed. Anyone could see that Rome would soon fall. It had never been easily defensible, and it was now little more than a ghost city. Spain, too, was already Muslim, its surviving Christian element driven into the mountain fastnesses of the north. France and the Franks would be next, or so it was assumed. The Muslim conquest of what is now Pakistan was under way. The vast, mysterious empire of China would dependably fall when Allah was ready to move his attention farther east.

Near at hand, the last remaining formidable Muslim objective was Constantinople, seat of the once-great Roman—Byzantine Empire, whose imperial rulers of late had behaved like madmen, and whose government was corrupt to the core. Its imminent demise was a foregone conclusion, the ruling caliph was confident, and this last and greatest conquest would assuredly spell the end of the fading religion known as Christianity.

For eight decades leading up to the fateful year 717, when the overwhelming naval and land forces of Islam would appear before Constantinople to deliver the final blow, one calamity after another had befallen the Christians. Indeed, it seemed to some that Christ himself had finally forsaken his people. The reversals went right back to the 630s and the reign of the emperor Heraclius, the man who lost Christendom to the Persians, and then heroically, even miraculously, snatched it back from them, only to see most of his empire conquered in a few short years by this ominous desert phenomenon, whose adherants called so assuredly and triumphantly on God, whom they named Allah.

From the catastrophic loss of Syria, Jerusalem, Palestine, and the impending fall of Egypt, Heraclius had headed home to his capital, enfeebled in body and mind. At Chalcedon, he could go no farther. Now afflicted by a pathological dread of water, he refused to make the half-mile crossing until a bridge of boats and barges was chained tightly together, piled with tons of soil, and bordered with high artificial hedges, so that he could ride over it without seeing the water. To such an absurdity had the world’s greatest empire been reduced. Ensconced in the imperial residence, he fell ill with dropsy, and suffered grievous affliction,1 while contemplating an empire sick at heart and sicker at soul.

Both Heraclius and Byzantium had been in desperate straits before, of course. Twenty-five years earlier, when he had roused the city to defend itself against the Persians and Avars, he had worked a startling moral reform. But the empire now seemed to have relapsed irretrievably into lethargy. Its neglected cities were wasting away. The ill-trained, ineffective army was often enmeshed in politics. The barbarians ravaged the provinces undeterred, killing, stealing and abducting. Learning was in hopeless decline. Meanwhile, in the provinces and the capital alike, the aristocracy continued to live in luxury described and deplored by the twentieth-century historian Prosper Boissonnade in Life and Work in Medieval Europe: “Their dwellings, half palaces and half fortresses, were elegantly decorated, spacious and beautiful. There they displayed all their luxury; their embroidered robes, their gold plate, gems, enamels, and precious silks, their table groaning under abundant foods, their stables full of fine horses and carriages.”

The church, too, was becoming steadily more dissolute. The Quinisext Council,2 held at Heraclius’s Trulla Palace a half-century after his death, would paint a detailed portrait of Christians reverting to pagan superstition and licentiousness. Canon 61 issued by that council would forbid soothsaying, the selling of tufts of wild animal hair as amulets, and the working of “enchantments.” Canon 63 would ban invocation of the god Dionysius at the grape harvest and other pagan festivities, with lewd dancing and male—female role reversal. The bishops would also find it necessary to forbid their clergy to run taverns, to act as loan sharks, charge for the sacraments, bathe with women, or serve as pimps. (Some historians warn, however, that fulminations heard at church councils do not necessarily reflect general Christian behavior, but unusual moral abuses.)

In the midst of social decline and personal agony, Heraclius died on February 11, 641, at the age of sixty-six. No deathbed description survives. He was “one of those unfortunate heroes who have outlived their glory, and have thereby won the sympathy as well as the admiration of posterity,” writes the historian J. B. Bury in his History of the Later Roman Empire. But Heraclius fared better in death than in life. “He passed into medieval legend,” Bury notes. By the twelfth century, he was celebrated in written romance and in heroic painting and sculpture, including a massive statue at Barletta, Italy.

Though precedents existed, many believed that Heraclius’s plan for the succession reflected the final frailty of his mind, and the machinations of his scheming wife, Martina. She was the niece he married after his first wife died, incurring the church’s denunciation for incest. He established a triumvirate–his eldest son Constantine III, twenty-nine, who had already ruled with him for seventeen years; Heraclonus, aged fifteen, his eldest son by Martina; and Martina herself. The immediate result was a ten-month feud in which Constantine III died (poisoned, some said, by Martina), in which the army was recalled from the Muslim front in Asia Minor to protect Constantine III’s children, and in which three emperors reigned at once. One of the three was banished, his nose slit;3 another simply disappeared. Martina was exiled by the Senate, after her tongue was silenced by being cut out. Finally Constans II, eldest son of Constantine III, was proclaimed emperor at age eleven.

Child though he was, Constans knew he had to grow up quickly. For his grandfather Heraclius, Islam had been only the nightmare of his final years; it was Constans’s principal threat from the start. In 646, when he was sixteen, an immense Byzantine fleet, sent to the relief of Alexandria, was decisively defeated near the harbor entrance. The Muslims then advanced along the African coast, taking first Barqa, then Tripoli. In 646, a Byzantine army striving to drive them from Syria was wiped out, and in 647, a 120,000-man Byzantine army was obliterated near Carthage. In 649, the Muslims, rapidly gaining naval power, pillaged Cyprus. In 651, they broke through into Asia Minor and returned to Syria with five thousand Christian slaves. That same year, a Byzantine attempt to save Armenia from Islam failed, and three years later, that ancient Christian country became an Islamic tributary state. The rich island of Rhodes fell in 655. Sicily went next. The eastern Mediterranean became a Muslim sea.

By now, Constans was twenty-five. Eager to do more than look on in helpless horror, he took personal command of a newly assembled Byzantine fleet. Although warned in a dream that he was headed for calamity,4 he ordered an attack on a Muslim squadron at Phoenix, off the southwest coast of Asia Minor. But as each ship came alongside an enemy vessel, the scimitar-swinging Muslims easily bested the Christians, and the decks ran red with their blood.

Changing garments with a sailor, Constans escaped by leaping from one ship to another, while one intrepid Byzantine soldier stood by the man who had donned the emperor’s clothes, fighting off the swarm of Muslims who sought to take the biggest prize of all, an imperial prisoner. Finally, both were slain, and the impersonation discovered–but not the emperor. The destruction of the Byzantine fleet in 655 would have spelled immediate doom for Constantinople if the Muslims had followed it up, but they could not. From 656, they were distracted by civil war, giving Constans a five-year breather, and in 659 the caliph, Mu‘awiya, agreed to a treaty.

In those five years, Constans executed his master plan to save the empire. With Egypt, Palestine, Syria and Armenia gone, and with Asia Minor and the eastern Mediterranean threatened, he concluded that Constantinople was doomed. Moreover, he intensely disliked the place. His theological effort to restore the unity of the faith, known as “The Type,” had been contemptuously rejected there (see subchapter, page 144), and its people continually demonstrated their disdain for him. He would therefore move his capital back to Old Rome, or better still, to Sicily. From there, he reasoned, he could safeguard Carthage, North Africa and Spain against Islam, recover Egypt, and eventually regain Italy from the Lombards.

His grandfather before him, reasoning likewise, had been persuaded to stay, but nobody pleaded with Constans to stay, and one final act sealed his reputation as a scoundrel. To secure the succession, he named his eldest son co-emperor, as Constantine IV, and probably bestowed the title of Caesar on his two younger sons. Then, to prevent rival claims, he quietly had his own younger brother executed. This, thought the capital, was cold-blooded murder.

Constans left for Italy with an army in 662, briefly occupied Naples, and then became the first eastern emperor in nearly three hundred years to visit Rome. He did more than visit; he stripped many Roman churches of their bronze statuary, hauling it all to Syracuse in Sicily, and for the next six years imposed such heavy taxes on North Africa and southern Italy that both verged on revolt. One day in 668, a bath attendant hit him over the head with a heavy soap dish, killing him in an apparent usurpation attempt. It failed. Constantine IV, his eldest son, arrived swiftly from Constantinople and summarily dealt with the conspirators.

All the while, the Muslim shadow across Asia Minor grew longer, darker, and ever closer to the capital. In 664, a Syrian raiding force actually wintered in Roman territory, a bad omen. Raids grew larger and deeper, until in the year of Constans’s assassination, Chalcedon was sacked, and its attackers withdrew only to Amorium, 160 miles to the southeast, for the winter. This time, however, young Constantine IV led a task force to Amorium, which scaled the walls over the deep snow and killed every Muslim in the place.

The caliph Mu‘awiya at Damascus could scarcely ignore such an affront, however, and having won his civil war, was free to embark on a crowning triumph. The time had come to capture the Christian capital, and perhaps the disreputable little barbarian Christian states beyond it as well. At sea, the Christians had no real navy left. Muslim land forces, although outnumbered four-to-one, or even ten-to-one, had invariably defeated the Christian empire’s decaying army. Mu‘awiya need only put a fleet on the Sea of Marmara, the 125-mile-long body of water between the Black Sea and the Aegean, sink the remnants of the Byzantine navy, and land an army in Constantinople’s Golden Horn Harbor.

By now, the Muslims were operating virtually unopposed in Asia Minor, raiding city after city. In 669, the year after Constans’s assassination, they attacked Sicily in force, carrying away, among other things, all the treasures Constans had amassed there for his new capital. In 670, two Muslim fleets moved through the Aegean and captured Smyrna, scene of the martyrdom of the saintly bishop Polycarp in the second century. (See earlier volume, A Pinch of Incense, page 58.) Then they transited the Hellespont,5 and set up a base at Cyzicus on the south coast of the Marmara.

But they had seriously underestimated Constantine IV. Still in his late teens, he supervised the construction of a new fleet of very small, very fast vessels that could attack like terriers, inflict telling damage, and then dodge away from the heavier Muslim ships–a seaborne version of the tactic that won so many Muslim land victories. Furthermore, the Byzantines were experimenting with a new and terrible weapon. Their fleet included several larger ships with a kind of spout protruding from the bow, which shot out an oily material intended to burst into flame on an enemy deck. Although not yet perfected, it was already spreading terror through the Muslim fleet.

Through the summer of 674, the Muslims patrolled the north coast of the Marmara without once attempting to land a soldier, and when winter came, retreated to their base at Cyzicus. So incessant were the Byzantine terrier attacks upon their fleet, and so increasingly effective the flaming oil, that this paralysis continued another two years. In 677, the Byzantine army in Asia Minor threatened the Muslim base at Cyzicus, leaving their fleet no option but to head for home, and it never got there. Caught by pursuing Byzantines at Syllaeum, off the south coast of Asia Minor, it suffered further grievous damage from the blazing oil, and then withdrew perforce into a ferocious storm that destroyed nearly all the remaining vessels.

The whole venture against Constantinople, in short, turned into one of Mu‘awiya’s few serious calamities, and forced him into an even more costly treaty. Constantine extracted from him payment of one pound of gold, one purebred horse, and one returned Christian slave for every day in the year. The treaty was to run for thirty years. The Byzantines wasted most of them.

Except, that is, in one regard: further development of their secret naval weapon, which came to be known as “Greek fire,” and is thought to have been discovered by a Christian Syrian architect named Callinicus. When the Muslims took over his homeland, Callinicus had made his way to Constantinople, where chemists and shipwrights worked to improve the incendiary potential of his invention, and perfect a way to project it. By the end of Mu‘awiya’s offensive, it had become the decisive weapon that saved the city. But the formula had to be kept secret–no mean trick in a city crawling with spies of every known nationality, which for the next forty years would be run by a succession of emperors whose incompetence still challenges belief.6

The Muslims had been learning, too. For one thing, they had discovered that Constantinople was not going to be another Antioch, Jerusalem or Alexandria, where theological feuds around the question of Monophysitism had so divided Christians that they could not unite to defend themselves. At Constantinople, they were not confused at all, and they knew by now what was at issue. If the city fell, the whole empire would become Islamic, the crosses would be stripped from the great churches, and most of them–beginning no doubt with mighty Hagia Sophia Cathedral itself–would become mosques. The Muslims, that is, were now up against an enemy as united in its religion as they were in theirs. So the capture of Constantinople–and captured it must be if Islam was to succeed–would require the biggest fleet and mightiest army they could possibly assemble.

And second, of course, they must somehow find out how to manufacture this Greek fire. That would not be easy either, for every inquiry they made produced the same answer. It came, said the Christians, from God and the Virgin Mary, who didn’t want the Muslims to have it.7 Greek fire became the most closely guarded secret in all Christendom, and the most sought by Christendom’s enemies.

With the death of Constantine IV, the downfall of the Heraclian dynasty accelerates. His son became Justinian II, whose yearning for personal glory was exceeded only by his incapability of achieving it. In exchange for amendments to the thirty-year treaty, for instance, he agreed to break up a Christian community known as the Mardaites, who for forty years had waged an effective guerrilla war against the Muslims in Asia Minor, often becoming a greater deterrent to them than the Byzantine army itself. Justinian moved most of the valiant Mardaites to the Danube region.

When the army protested the loss of these valuable allies, Justinian recruited a dubious contingent of barbarian Slavs instead, and led them against the Muslim army in Asia Minor. After two-thirds of the Slavs deserted to the Muslims, however, Justinian fled with the loyal third–all of whom he then executed because he was so furious with their faithless comrades. His two senior treasury officials meanwhile became so ruthless in their tax exactions that the populace rose against them, tied their feet together, and dragged them to death through city streets, then publicly burned their bodies. They next seized the emperor himself, slit both his nose and tongue, banished him to the Crimean Peninsula in the Black Sea, and proclaimed as emperor the individual who had led them in this rebellion.

This man, Leontius, inaugurated the first of seven imperial regimes that for two terrible decades would preside over the disintegrating empire while the Muslims made ready to finish it off. Leontius’s regime, lasting three years, was distinguished only by the decision of the Roman governor of Lazica, on the Armenian frontier, to convert to Islam and take the province over with him. Leontius was succeeded by Apsimar, a general who headed a military revolt in southern Asia Minor, led his army against the capital, slit Leontius’s nose, banished him to a monastery, and flogged and deported his senior officials.

Apsimar, declaring himself Tiberius III, launched an offensive against the Muslims in Syria. It failed. Armenia meanwhile rose in revolt against its Muslim masters. This too failed, and the Muslims, keen to discourage such conduct, burned the flower of the Armenian nobility to death in a church, along with their wives and children. (See sidebar, pages 260—261.) During his seven-year tenure, however, Tiberius did one thing well: He put his brother in command of the army on the Asia Minor front, and it inflicted two costly defeats on the Muslim forces, thereby delaying their planned attack on Constantinople.

Next followed one of the strangest and most tragic comebacks known to history. Justinian II, furiously brooding in his exile at Chersonesos, a semi-independent trading city on the Crimean Peninsula, plotted the recovery of his throne, split nose and tongue notwithstanding. Justinian was a man of great courage and relentless ambition, most historians agree, but by now was almost certainly insane. Fearing the wrath of the reigning emperor, Chersonesos’s officialdom decided to assassinate him.

Apprised of the plot, Justinian fled the city and appealed for help to the wild and wily Khazars, who lived near the Black Sea’s north coast. Their chief, the khagan, flattered that the direct descendant of the revered Heraclius should become indebted to him, offered him protection, and gave him his sister in marriage. Emulating his namesake, Justinian the Great, the exiled emperor named his new wife Theodora. Tiberius, thoroughly alarmed, bribed the khagan to get rid of this unexpected challenger, and the khagan commissioned two officials to kill his newly acquired brother-in-law. But Theodora warned her husband, who invited the would-be assassins to dinner, one at a time, and personally strangled them.

Events now moved swiftly. Justinian commandeered a fishing boat, gathered the few officials who had remained loyal to him in exile, sailed along the Black Sea coast8 and up the Danube, and there made a deal with the king of the Bulgars. For help in regaining his throne, he would bestow upon the Bulgar king the rank of caesar–an offer a barbarian king couldn’t refuse. Thus Justinian marched on Constantinople at the head of a Bulgar army reinforced by other Slavs, camped outside the walls, and declared that the rightful ruler, the descendant of Heraclius, had returned to claim his throne. The gates were mysteriously opened. Justinian took up residence unopposed in the Blachernae Palace–and unleashed upon the city a vindictive vengeance of appalling cruelty.

Tiberius was caught fleeing and brought back in chains. From his tranquil monastery the unfortunate Leontius was also dragged away. Both were paraded through the streets, then at the Hippodrome made to crouch before Justinian, who planted his feet on them. After this soul-satisfying ceremony, Justinian had them taken away and beheaded. Tiberius’s brother, victor over the Muslims in Asia Minor, was returned to the city and hanged, together with all his senior officers. The patriarch was blinded and exiled to Rome. Special treatment was reserved for senior government officials, such as entertainment at a sumptuous official banquet, at the conclusion of which they were either hanged or decapitated.

Against Chersonesos, Justinian successively sent three fleets. The first brought the city’s leaders to Constantinople, where they were publicly roasted on spits. The second, carrying thousands of Chersonese prisoners destined for death or slavery, sank in a storm. The third fleet had orders to burn the city to the ground and kill anybody left alive there, but turned instead against Justinian, proclaimed their Armenian commander Bardanes as the emperor Philippicus, and prepared to seize the capital. The timing of these massive naval expeditions is noteworthy; they occurred in 710 and 711, just when Muslim armies were crossing the Strait of Gibraltar to effect the conquest of Spain. The invaders made their crossings completely unresisted, because the Byzantines had no vessels to oppose them. Their ships were too busy wreaking Justinian’s vengeance on Chersonesos.

With the arrival of Philippicus, troops previously loyal to the mad emperor deserted him. He was executed forthwith by a sword thrust, and Theodora was also slain. Their six-year-old son was sheltered by his grandmother in a Constantinople church, where he clung to the altar with a piece of the true cross in his hand and a number of relics hung about his neck. Thrusting aside the shrieking grandmother, an officer removed the sacred wood from the child’s hand and laid it carefully on the altar. He next took the relics from his neck and hung them about his own. Finally, he carried the little boy to the church gate, stripped him, and cut his throat like a sheep’s. Thus died the last representative of the house of Heraclius.

Philippicus, in his two-year reign, seemed more interested in the rewards of office than its duties. While he gained a reputation as a voluptuary, army morale sank perilously, and the Muslim takeover of Asia Minor began in earnest. In 712, they moved in force into Pontus and seized Amasya, only sixty miles from the Black Sea coast. The next year, they overran Antioch in Pisidia, the base for St. Paul’s missionary work in eastern Asia Minor. By now, however, the army had had enough of Philippicus. The soldiers seized him after a bounteous morning banquet with his friends, blinded him, and replaced him with his secretary, Anastasius.

Anastasius was not long in office before alarming reports began coming in from Damascus, where the Muslims were said to be engaged in a vast military buildup, constructing siege equipment of all kinds. From Alexandria came information that timber was being imported from Lebanon, warships built by the hundreds, and crews trained. Clearly, a huge invasion was imminent.

Anastasius, who was no fool, immediately directed that the walls of Constantinople be repaired and strengthened, and stationed anti-siege equipment atop them. All citizens must provide themselves with a three-year supply of food, he ordered, or leave the capital immediately. He further ordered what a later generation would call a “preemptive strike,” an attack on the Muslim shipyards and timber supplies. But the troops assigned to this task had politics of their own. One of the key regiments (“themes,” as they were called) assigned to the attack renounced its loyalty to Anastasius. Instead of attacking the enemy, they made for Constantinople to attack the emperor.

Their next move is close to incredible. Realizing en route that they had no replacement for Anastasius, they seized a minor official named Theodosius (he had an imperial name, at least) and informed him he was to be emperor. The man fled in abject fear to the mountains, but they tracked him down, took him along to the city, deposed Anastasius without harming him, and declared their terrified candidate to be Theodosius III Augustus. The Muslim buildup meanwhile continued unabated. What but a miracle could save Christendom now?

The Christians assuredly must have been praying for one, and what they received in response was a new and very different emperor. He is known as Leo the Isaurian. Isauria was the region in central Asia Minor where Paul and Barnabas had established some of their first missions nearly seven hundred years earlier. (Some accounts, however, make Leo a Syrian.) The chroniclers say that his given name was Conon and that his father, seeking a position for his son, presented Justinian II with five hundred sheep. In return, Leo was designated an imperial aide-de-camp.

But Justinian, growing suspicious of his new aide, sent him off as an emissary to the tribes beyond the Black Sea, where he intended him to be assassinated. Instead, after a number of hairbreadth escapes, Leo got back to Constantinople, where he found that Justinian himself had just been assassinated. His reputation for intrepidity established, Leo was given command of the defense of Asia Minor. This task he fulfilled so well that as the Muslim attack became ever more imminent, he became the obvious candidate to succeed the hapless Theodosius. On March 25, 717, he was crowned Leo III, Theodosius having gratefully (and safely) abdicated. Leo had five months left to prepare for the most massive attack the city had ever confronted.

No adult in Constantinople was under any illusion as to what was in store. They knew there could be no question of surrendering without resistance, and therefore no hope of clemency if the Muslims were to take the city. The prospects in case of defeat were grim: slavery for able-bodied male survivors; rape and slavery for young women and for comely, pubescent boys; death for the valueless elderly. Everything marketable and movable in the empire’s most opulent city would be hauled away–a staggering trove. To the defenders all this was the stuff of nightmare, but to the attackers, the stuff of fondest dreams. There had been no problem recruiting armies for the sack of Constantinople.

Then came the rumors. An enormous and heavily equipped Muslim army, tens, perhaps hundreds of thousands of men, was moving across Asia Minor unopposed. Men said that a fleet, far bigger than anyone could remember, was bound for Constantinople from Tarsus, birthplace of St. Paul. Meanwhile, Leo–cool, efficient, rational, and as always, wholly practical–made every day count.

On August 15, the rumors became hideously true. Crossing the Hellespont from Asia Minor, an army of eighty thousand men under Moslemah, brother of the caliph, Suleyman, came within sight of the city’s four-mile long walls. The defenders looked on aghast as rank upon rank of heavily armed warriors appeared, and mammoth siege engines were dragged up. There were catapults to hurl great boulders at the ramparts. There were towers that would be worked forward to lean against the walls, whence screaming attackers could overtop them to slay the defenders.

The gates shortly opened, and an embassy from Leo emerged and paced towards the Muslim line. The emperor offered one gold piece for every person in Constantinople if the attacking army would withdraw, a generous and very costly gesture that would weigh heavily on his people, if accepted. But Moslemah was a realist. His men had been recruited with far greater spoils in mind. Anyway, how could the fleets of ships now on their way to the Sea of Marmara be turned back? Furthermore, this extraordinary offer must mean Leo figured he couldn’t win. Moslemah haughtily rejected it, and ordered the attack.

To deafening cheers from the Muslim ranks, the big rocks crashed into the walls. The more daring assailants dashed in, to hurl up their grappling hooks. The siege towers lurched forward. Then, from the walls came a ghastly phenomenon: some kind of oily material that poured down on the most advanced attackers, bursting into flame and seemingly flying about everywhere. Men shrieked in pain and fled frantically, but the fire itself clung tightly to them, and nothing would extinguish it.

Next came another horror. Stones, catapulted back from the wall tops, smashed into the siege towers and seemed to burst, spreading the same flaming substance and completely destroying them. Strange arrows, carrying a kind of pouch, and raining down on the ranks of the Muslim cavalry and infantry, also spewed flaming oil that splashed far and wide. Men and horses panicked and ran insanely as their flesh burned away.9

Moslemah, sizing up the attack as hopeless, quickly signaled a retreat. As his men fled back to the Muslim line, another cheer went up, this one from the Christians. Islam’s supposedly invincible army, hitherto universally victorious in almost everything it undertook, was fleeing in terror from its first assault on the Christian capital.

But the siege had only begun. While Moslemah’s men built a massive stone breastwork behind which his troops could take cover, he reached a reluctant conclusion. He must starve the city into submission. How he proposed to accomplish this became plain two weeks later. Constantinople awoke on the morning of September 1 to find that the familiar Sea of Marmara had become overnight a moving forest of ships’ masts, a fleet that stretched as far as the eye could see, small vessels and large, eighteen hundred in all. Aboard it, they would later discover, were another eighty thousand soldiers, under the command of an admiral named (like the caliph) Suleyman. How could such an armada ever be stopped?

Leo was studying this fleet from a somewhat different perspective–looking for spouts on the bows of the lead vessels, and catapults on their decks. The outcome, he knew, depended on a single question: Had the formula been safeguarded? Had the Muslims acquired Greek fire? He had seen no sign of it in their army. Now he could see none in their navy. So the secret had been kept, a triumph of counterespionage. His deplorable predecessors had somehow accomplished this one thing–and it was the only thing that mattered.

Next day, the Muslims found out why. They divided their huge fleet. Half was to sail through the Bosporus to its junction with the Black Sea and block supplies from principal centers like Chersonesos in the Crimea and Trebizond on the south coast. The remaining ships would blockade it from the west, cutting off access from the Aegean. But as the first big vessels began rounding Seraglio Point at the entrance to the Golden Horn harbor, their captains noted a surprising change. The great chain that crossed the harbor mouth from towers on either side, to block enemy vessels from entering, had been dropped. The harbor was wide open. Was this some kind of trick?

As the swift current on the point swirled their vessels about, the gruesome explanation was revealed. Out of the harbor like a pack of wolves came a squadron of little vessels, biremes with two tiers of oars, each equipped with some kind of launching device. Though the Muslims didn’t know it, the emperor himself was in one of them. The hundred or more soldiers aboard each big Muslim vessel grasped their scimitars and waited to pounce upon the much smaller Christian crews. But the little ships abruptly stopped short of them, and from them flew some kind of projectile.

Muslim captains who had heard accounts of Mu‘awiya’s siege forty years before may have guessed what this was. But it now came far more accurately, far more lethally, bursting into flame on their crowded decks, and spreading a raging fire upward into the rigging and in a wide arc all around. The men, their very skin on fire, went berserk. Many dove into the sea, only to find that the water would not put the fire out; when the substance again touched air, it burst into flame once more. Within perhaps an hour, twenty vessels had burned and sunk. Others were wrecked as they crashed crazily into each other. Some had been abandoned and captured. The rest escaped back to the Marmara. This left the path to the Black Sea still open, and through it, Christian vessels day by day brought tons of supplies into the capital.

Moslemah pondered his preposterous situation. He had enough men and ships to take the city five times over, and more on the way, but he couldn’t get near the enemy’s vessels, nor attack the enemy’s walls. Dumbfounding as it might seem, the sensible thing was to call off the whole expedition, but the consequence to Muslim prestige, he knew, would be devastating. What was to be done? Plainly, he must consult his brother.

About then, the next blow fell. The caliph Suleyman was at Tarsus, in personal command of a replacement contingent being trained there to reinforce the invasion troops. On October 8, however, his digestive system failed, and he suddenly died.10 The withdrawal decision was therefore up to his successor, Umar II, a man as strong on theology as he was weak on warfare. Umar’s decision was to not decide, which prolonged the siege into the winter–an eventuality for which the besiegers, having expected a swift victory, seemed to have been utterly unprepared.

The seaborne fighters were put ashore, and the fleet set at anchor. Soon the snow arrived, something many recruits from Arabia, Persia, Syria and Egypt had never before seen. It came and it stayed . . . and stayed . . . and stayed. For more than three months of this unusually severe winter, according to the records, bare ground could not be seen. At the same time, while Constantinople dined frugally but adequately, the besiegers themselves suffered mortally from the starvation they planned to inflict upon their enemies. Before long, the hundred and fifty thousand Muslim troops had eaten all their horses and camels, and were subsisting (says one account) on a mixture of boiled human flesh and excrement. Disease spread, the death toll rose into the thousands, and among the dead was the admiral Suleyman, commander of the Muslim fleet.

Finally the spring of 718 came, and with it a supply fleet from Alexandria, some four hundred ships in all. Many began making their way through the Bosporus by night. It was then that another development heartened the defenders, although how it happened can only be conjectured.11 The sentries at the entrance to the Golden Horn likely heard the splash of oars from a small boat out on the bay, since even a slight sound will travel far over calm water at night. Then they must have realized it was not one small boat but several, maybe a dozen, maybe more–a veritable squadron of little boats. What could this be? The Muslim army would not attack in rowboats, and whoever it was seemed remarkably noisy, for soon voices could be heard.

Many voices, it seemed, calling something in unison. It was Greek–they were definitely speaking Greek. Then words became discernible: “Long live the emperor!” As the little boats reached shore, the Byzantine guards doubtless stood alert with swords drawn. The men tumbled out, and with them came their story. They were Christians, they said, pressed into slavery on the Muslim vessels. Having long planned to escape at Constantinople, they had overcome their guards and dumped their officers into the sea. These few had escaped in the ships’ boats, while the rest took charge of the ships, and were awaiting orders from shore. The thought may have dawned on some Byzantines that most or all of these men must be Monophysite Christians. But what did that matter now?

Their liberated vessels were now drifting out there in the dark, they said. Very quickly, the agile Byzantine fireboats went into action, guided by the Christian mutineers. The seized ships were taken over; their former crews, now freemen, rowed them into the Golden Horn as prizes of war. Meanwhile, Greek fire wreaked a further toll on the rest of the Muslim fleet.

From this incident came another dividend. Leo now knew how many Muslim ships there were, what they were carrying, how they were armed, and also that another Muslim fleet, in fact the third, was sailing in from North Africa. He seems, from subsequent events, to have discovered something else, namely that the late caliph’s replacement army was said to be nearing Constantinople, with no reason to expect an attack. Leo acted immediately. A task force dispatched across the Bosporus confirmed this intelligence and ambushed the army, claiming uncounted casualties and routing the rest. Thus, the Muslim thousands lost to cold, disease, starvation and Greek fire were not replaced. Further, the Byzantine force established fishing stations on the opposite shore to ensure the city a daily supply of fish.

When the third fleet arrived, 360 ships this time, it anchored on the Marmara’s south coast and stayed there. It had been ordered to reinforce the Black Sea squadron, but its commander judged the risk too high. Some ships from the second fleet had made it through and were blockading the Black Sea approach to the city, but this, too, availed them little because Leo had one card left to play, and it would prove decisive.

The Bulgars, who had launched an ineffective attack on Constantinople after the assassination of Justinian II, had for some time been engaged in treaty talks with Leo’s emissaries. By the spring of 718 they reached agreement, and soon a motley army of Bulgars and Slavs advanced southward against what remained of Moslemah’s army, still camped outside the city walls. Moslemah marched north to meet them near the city of Adrianople, 125 miles to the northwest, scene of the empire’s decisive loss to the barbarian Visigoths 340 years before. (See earlier volume, Darkness Descends, chapter 3.) Here Moslemah suffered a major defeat. Thus the barbarians, having first beaten the empire at Adrianople, now played a decisive role in saving it there.

This reversal, coupled with a false rumor (spread by Leo) that the fearsome Franks were also on their way to save the Christian capital, caused Umar to make up his mind. He ordered his troops to retreat. On August 15, 718, one year to the day after their arrival, the Muslim soldiers departed, transported across the Hellespont by the remainder of their navy. Yet even this was not the end. As the still considerable fleet sailed into the Aegean, a fierce and unseasonable storm drove much of it onto the rocks. On the south coast of Asia Minor, an even worse storm reportedly sank all but ten vessels. Then a small Byzantine force that had been shadowing the Muslim ships closed in and sank five. So only five ships reached Tarsus–of the approximately twenty-five hundred that descended so confidently on the Christian capital the year before.

Military historian J. F. C. Fuller (The Decisive Battles of the Western World) estimates that in all, two hundred-thousand men took part in the siege, and about thirty thousand survived it. “The Siegel of Constantinople would have remodeled the entire history of the East,” he writes. “Beyond question, the Muslim repulse was one of the great decisive events in Western history.”

J. B. Bury calls the failure of the siege “ecumenical,” implying that it pivotally affected all history. Harry Turtledove, in the introduction to his translation of Theophanes, says that if Constantinople had not survived, “the history of the world would have been incalculably different.” Such a defeat for the Muslims, observes C. W. C. Oman (The Byzantine Empire), “was well calculated to impress on their fatalistic minds the idea that Constantinople was not destined by Providence to fall into their hands.” It would stand as a Christian bastion against Islam for another 735 years.

Other conclusions can be drawn. One is the fact that the Christian victory was one of technology over mere mass and multitude. So thoroughly did the Byzantines safeguard the formula for Greek fire that to this day, no one is altogether sure what it was, though it must have been based on naphthalene. Equally significant is the fact that the Muslims had seen Greek fire in its early stages forty years earlier, but fatally underestimated its possibilities. They would soon demonstrate themselves every bit as intelligent as Christians (and frequently more virtuous), but never did they give the same attention to the physical sciences as would the Christians. This would tell against them right through to the twenty-first century.

The chronic weakness of the Christians was becoming similarly plain: what an old Anglican prayer calls “our unhappy divisions.”12 Almost every historical account agrees that Syria, Palestine, Egypt, and North Africa fell to the Islamic invaders because the populace had been so bitterly alienated by brutally zealous imperial efforts to stamp out Monophysite Christianity. But with Islam checked, the initiative now moved to the Christian side, and the story must next be told of how the Christians spread their faith northward and eastward, thereby laying the foundations of Western civilization.

This is the end of the Siegel of Constantinople category article drawn from Chapter Ten, beginning on page 255, of Volume Five, The Sword of Islam. To continue reading more about Siegel of Constantinople from The Christians, Their First Two Thousand Years we suggest experiencing the rest of the book, complete with hundreds of magnificent illustrations, by ordering it at