Siege of Constantinople, 717 CE

The Top 3 Deadliest Sieges Before the 19th Century

Sieges throughout history were awful affairs. Unlike Field Battles, Sieges involved civilians, as well as numerous ways to die over long periods of time. Starvation and disease often killed about as many soldiers and civilians as actual fighting did.

It wasn’t until the 19 th and 20 th century where guns, artillery and air strikes were able to inflate the casualties to over a million as at Stalingrad, but some ancient and medieval sieges were outstandingly epic affairs involving hundreds of thousands of people. Sieges quite often turned the whole tide of a war while also leaving an unimaginable scar on the besieged population.

Believe it or not, the two sieges of Jerusalem just missed the top three for most deadly. the 70 CE siege by Rome and the capture by the Crusaders in 1099 were still terrible losses of life.

The Siege of Constantinople, 717-718 AD – The Use of Naval Power

“[They] began blowing with smiths’ bellows at a furnace in which there was fire and there came from it a great din. There stood there also a brass [or bronze] tube and from it flew much fire against one ship, and it burned up in a short time so that all of it became white ashes…”

a possible eyewitness account of Greek Fire from the 12th-century Norse saga,Yngvars saga víðförla

Although many still believe that the Roman imperial order collapsed with the fall of the Western Empire in 476, in reality, it continued on for almost another millennia in the form of the Eastern Roman (or Byzantine) Empire. From their palaces in the famed city of Constantinople, the Byzantine emperors attempted to preserve the imperial remnant in the face of mounting challenges from all sides.

Crucial to this imperial project was maintaining control over the eastern half of the Mediterranean. Continuing the naval traditions inherited from their predecessors of the Classical Era, the Eastern Empire was almost alone in producing and deploying dedicated fleets of warships – mostly consisting of sleek and swift dromons, a moderately improved version of the older Roman liburnae galleys. And exploiting this technological edge, the Byzantines deployed fleets that allowed them to exercised considerable control over the vast amounts of trade and wealth that continued to flow from Asia into Europe via their sea lanes. This initial Byzantine advantage, however, did long go unchallenged.

Map of the main Byzantine-Muslim naval operations and battles in the Mediterranean, 7th–11th centuries – image by Cplakidas / Wikimedia Commons

In the seventh century, the Islamic Conquests burst out of Arabia like a sandstorm, devouring almost every other nation on their periphery for nearly a century, including the Byzantine provinces of Egypt, the Levant, and Syria. Proving themselves remarkably adaptable, the Arab caliphates began building and deploying fleets of their own and established themselves as dangerous competitors for control of the Mediterranean. Soon, there was not a coast within the Middle Sea that did not experience Arab sea raids or piracy.

In the early years of the eighth century, the head of the Umayyad Caliphate, Sulayman ibn Abd al-Malik, sought to escalate Arab ambitions even further and dispatched a massive army with an accompanying fleet to capture Constantinople itself. Although Arabs had attempted such a move before and failed, Sulayman was convinced this time would be different, taking advantage of a prolonged period of internal civil conflict and imperial coups within the Eastern Empire – those two being the perennial weaknesses of the Byzantine state. The army, numbering potentially in the tens or even hundreds of thousands, would lay siege to the city by land on its western front and the fleet would blockade its eastern approaches via the sea in the Hellespont. The Arab forces were in place before the walls of Constantinople by the year 717.

However, almost from the start, the tide went against the Arabs. Right before the siege began, the Imperial Crown came to rest on the brow of the extremely capable Leo III, who brilliantly prepared his new capital city for the impending siege. Rapidly making alliances with key powers within and without the Empire, marshaling Roman forces to fortify pivotal avenues of approach in the Aegean and Asia Minor, and ensuring each citizen stockpiled three years of supplies within the city itself, Leo was more than ready to face the Arab onslaught.

The defenses on the landward side of Constantinople were legendary, consisting of the famed triple-layered Theodosian Walls built by their namesake, Theodosius II, in the fifth century. The Arab army was remarkably short on siege equipment and seemed to rely solely on the tactic of starving out the city by means of a joint land and sea blockade.

On 3 September 717, the Arab commander, Maslama, ordered his fleet to reposition farther up into the Hellespont to cover the Golden Horn and the Byzantine sea lanes coming from the Black Sea. As the Arab ships made their way north, their inexperienced sailors lost the wind and slowed to a confused gaggle right at the entrance to the Golden Horn. Leo seized this moment and launched his trump card – a fully armed Byzantine fleet hiding in the Golden Horn equipped with the terrifying secret incendiary weapon named for its inventors, Greek Fire. Taken on the flank and caught completely by surprise, the Arabs lost twenty ships with all hands in an instant to the napalm-like substance that the Byzantines had developed to jet out in a directed stream from bronze siphons on their ships like described above in the quotation. The survivors scattered southward, abandoning the waters to the Byzantines for the rest of the siege.

From there, the fortunes of the besieging Arabs went from bad to worse. Two resupply fleets met the same fate as the first, and the Arab army found itself dying of disease and starvation before the impregnable walls of Constantinople in a particularly harsh Thracian winter. The situation became so desperate for them that, according to Theophanes the Confessor – the main primary source for the siege – the besiegers resorted to eating their pack animals, plant sprouts, feces, and even their own dead. Finally, an army of Bulgars allied with Leo descended upon the Arabs and slaughtered them nearly to a man. Of the fleet of hundreds of vessels that the Arabs dispatched, allegedly only five returned.

The year 718 would mark the final Arab attempt to take the fabled city of Constantinople, such an outcome due in no small part to the actions of the Imperial Navy and their horrific Greek Fire. Three decades later, the Umayyad Caliphate would collapse and give way to the Abbasids, who relocated their capital from Damascus to Baghdad and never again substantially challenged Byzantine maritime power.

Despite playing such a pivotal and dramatic role repeatedly in Byzantine naval warfare, there exists no clear idea of what exactly Greek Fire was or how it was made – its creators taking the finer details of their prized secret weapon with them to their tombs. It was obviously some sort of petroleum-based compound that could be directed in an ignited liquified stream through siphon mechanisms installed at the prows of specialized warships built for that purpose.

Some historians debate the importance of Greek Fire and question its role in securing Byzantine maritime success during that period. These would argue that it was, in fact, merely their continuation of Classical Roman naval organization and professional traditions that truly enabled the Eastern Roman Empire to project sea power into the Mediterranean. Whatever the case, the Imperial Navy was possibly the most formidable naval force roaming the Mediterranean in the early centuries of the medieval era and many challengers were sent to the bottom in a literal weaponized firestorm.

Dr. Andrew Latham is a professor of political science at Macalester College in Saint Paul, Minnesota. He is the author, most recently, of a monograph entitled Medieval Sovereignty, to be published in 2020 by ARC Humanities Press. You can visit Andrew’s website at or follow Andrew on Twitter @aalatham

Rand Lee Brown II is a recently retired officer in the United States Marine Corps. Holding a Master of Arts degree in Military History from Norwich University with a focus on medieval warfare, he has written on military history for a variety of forums, including the Marine Corps Gazette and

Further Reading:

Stanton, Charles D. Medieval Maritime Warfare (Pen & Sword Books, 2015)

Whittow, Mark. The Making of Byzantium 600-1025 (University of California Press, 1995)

Top Image: Image from the Madrid Skylitzes, showing Greek Fire in use against the fleet of the rebel Thomas the Slav

Constantine I

Constantine set about expanding the territory of old Byzantium, dividing it into 14 sections and constructing a new outer wall. He lured noblemen through gifts of land, and transferred art and other ornaments from Rome for display in the new capital. Its wide avenues were lined by statues of great rulers like Alexander the Great and Julius Caesar, as well as one of Constantine himself as Apollo.

The emperor also sought to populate the city through offering residents free food rations. With a system of aqueducts already in place, he ensured access to water through the widening city by the construction of the Binbirdirek Cistern.

In 330 A.D., Constantine established the city that would make its mark in the ancient world as Constantinople, but also would become known by other names, including the Queen of Cities, Istinpolin, Stamboul and Istanbul. It would be governed by Roman law, observe Christianity and adopt Greek as its primary language, although it would serve as a melting pot of races and cultures due to its unique geographic location straddling Europe and Asia.

Opening stages of the campaign [ edit | edit source ]

Gold solidus of Anastasios II (r. 713–715), who prepared Constantinople for the coming Arab assault

The Arab successes opened the way for a second assault on Constantinople, an undertaking already initiated under Caliph al-Walid I (r. 705–715). Following his death, his brother and successor Sulayman (r. 715–717) took up the project with increased vigour, according to Arab accounts because of a prophecy that a Caliph bearing the name of a prophet would capture Constantinople Sulayman (Solomon) was the only member of the Umayyad family to bear such a name. According to Syriac sources, the new Caliph swore "to not stop fighting against Constantinople before having exhausted the country of the Arabs or to have taken the city". ⎗] The Umayyad forces began assembling at the plain of Dabiq north of Aleppo, under the direct supervision of the Caliph. As Sulayman was too sick to campaign himself, however, he entrusted command to his brother Maslama ibn Abd al-Malik. ⎘] The operation against Constantinople came at a time when the Umayyad state was undergoing a period of continuous expansion to the east and west. Muslim armies advanced into Transoxiana, India and the Visigothic Kingdom of Hispania. ⎙]

Arab preparations, especially the construction of a large fleet, did not go unnoticed by the worried Byzantines. Emperor Anastasios II (r. 713–715) sent an embassy to Damascus under the patrician and urban prefect, Daniel of Sinope, ostensibly in order to plea for peace, but in reality to spy on the Arabs. Anastasios, in turn, began to prepare for the inevitable siege: the fortifications of Constantinople were repaired and equipped with ample artillery (catapults and other siege weapons), while food stores were brought into the city. In addition, those inhabitants who could not stockpile food for at least three years were evacuated. ⎚] Anastasios strengthened his navy and in early 715 dispatched it against the Arab fleet that had come to Phoenix—usually identified with modern Finike in Lycia, it is may also be modern Fenaket across Rhodes, ⎛] or perhaps Phoenicia (modern Lebanon), famed for its cedar forests ⎜] —to collect timber for their ships. At Rhodes, however, the Byzantine fleet, encouraged by the soldiers of the Opsician Theme, rebelled, killed their commander John the Deacon and sailed north to Adramyttium. There, they acclaimed a reluctant tax collector, Theodosios, as emperor. ⎝] Anastasios crossed into Bithynia in the Opsician Theme to confront the rebellion, but the rebel fleet sailed on to Chrysopolis. From there, it launched attacks against Constantinople, until, in late summer, sympathizers within the capital opened its gates to them. Anastasios held out at Nicaea for several months, finally agreeing to resign and retire as a monk. ⎞] The accession of Theodosios, who from the sources comes across as both unwilling and incapable, as a puppet emperor of the Opsicians provoked the reaction of the other themes, especially the Anatolics and the Armeniacs under their respective strategoi (generals) Leo the Isaurian and Artabasdos. ⎟]

Map of Byzantine Asia Minor and Thrace in the early 8th century

In these conditions of near-civil war, the Arabs began their carefully prepared advance. In September 715, the vanguard, under general Sulayman ibn Mu'ad, marched over Cilicia into Asia Minor, taking the strategic fortress of Loulon on its way. They wintered at Afik, an unidentified location near the western exit of the Cilician Gates. In early 716, Sulayman's army continued into central Asia Minor. The Umayyad fleet under Umar ibn Hubayra cruised along the Cilician coast, while Maslama ibn Abd al-Malik awaited developments with the main army in Syria. ⎠]

The Arabs hoped that the disunity among the Byzantines would play to their advantage. Maslama had already established contact with Leo the Isaurian. French scholar Rodolphe Guilland theorized that Leo offered to become a vassal of the Caliphate, although the Byzantine general intended to use the Arabs for his own purposes. In turn, Maslama supported Leo hoping to maximize confusion and weaken the Empire, easing his own task of taking Constantinople. ⎡]

Sulayman's first objective was the strategically important fortress of Amorium, which the Arabs intended to use as a base the following winter. Amorium had been left defenceless in the turmoil of the civil war and would have easily fallen, but the Arabs chose to bolster Leo's position as a counterweight to Theodosios. They offered the city terms of surrender if its inhabitants would acknowledge Leo as emperor. The fortress capitulated, but still did not open its gates to the Arabs. Leo came to the vicinity with a handful of soldiers and executed a series of ruses and negotiations to garrison 800 men in the town. The Arab army, thwarted in its objective and with supplies running low, withdrew. Leo escaped to Pisidia and, in summer, supported by Artabasdos, was proclaimed and crowned as Byzantine emperor, openly challenging Theodosios. ⎢] ⎣]

Gold solidus of Leo III

Leo's success at Amorium was fortunately timed, since Maslama with the main Arab army had in the meantime crossed the Taurus Mountains and was marching straight for the city. In addition, as the Arab general had not received news of Leo's double-dealing, he did not devastate the territories he marched through—the Armeniac and Anatolic themes, whose governors he still believed to be his allies. ⎤] On meeting up with Sulayman's retreating army and learning what had transpired, Maslama changed direction: he attacked Akroinon and from there marched to the western coastlands to spend the winter. On his way, he sacked Sardis and Pergamon. The Arab fleet wintered in Cilicia. ⎥] Leo, in the meantime, began his own march on Constantinople. He captured Nicomedia, where he found and captured, among other officials, Theodosios's son, and then marched to Chrysopolis. In spring 717, after short negotiations, he secured Theodosios's resignation and his recognition as emperor, entering the capital on 25 March. Theodosios and his son were allowed to retire to a monastery as monks, while Artabasdos was promoted to the position of kouropalates and received the hand of Leo's daughter, Anna. ⎦]

The Umayyads conquer Constantinople in 717

Do you know the numbers on each side wrt the Siege of Constantinople?

Wiki says that the Byzantines were severely outnumbered but still won the decisive battle. What are your thoughts on the numbers provided by wiki?


Do you know the numbers on each side wrt the Siege of Constantinople?

Wiki says that the Byzantines were severely outnumbered but still won the decisive battle. What are your thoughts on the numbers provided by wiki?





Total imperial army was 300.000-450.000, it depends when. I think that Septimius Severus was having 450.000 or close to it. At end of republic all parties were fielding over 50 legions and Augustus has kept 28. But number of auxilia was same as of legionaries. 28 full legions were 168.000 and with auxilia total around 330.000 or so. Later number of legions was 30 and 32.

At Each Kilometer



This was also few decades before railroads.

Or the biggest battle of 17th century
280.000 men
Battle of Berestechko - Wikipedia


The ummayyads cared more about money and commerce than they did for religious fanaticism. They would probably make the jewel of the world, Constantinople, their capital. When the Abbasid revolt did occur, the empire would probably split along the Roman and Persian lines rather than the abbassids being as successful in overtaking the entire empire except Spain. I could see the ummayads being more tolerant of alcohol use which would end up with a Muslim Russia. I would be surprised if Bulgaria and Hungary also didn’t become Muslim as well. So christemdom May be kept to the empire of Charlemagne borders and the British isles.

I see the ummayads seeing themselves as successors of the Roman Empire as controlling the east capital, Africa, and Spain, so they may seek to reunify the Roman Empire under the banner of the green moon. The dark age may be seen associated with Christianity and that religion may fade. Or since Islam still isn’t viewed as an entirely different faith, they would view Islam as the right path chosen by the Abrahamic god.

What We Learned From… The 717-18 Siege of Constantinople

The 632 death of Muhammad, the unifying Arab military leader and founder of Islam, presaged the beginning of the Muslim conquests that over ran much of the Middle East and North Africa. By the early 8th century Muslim armies of the Umayyad caliphate stood poised on Europe’s doorstep, with the Byzantine capital of Constantinople as their primary obstacle.

In 717 the Umayyad Caliph Sulayman, looking to kick open the door to the Continent, sent his brother Maslama against Constantinople with an army of at least 80,000 men and a fleet of some 1,800 galleys. Facing them were a vastly outnumbered garrison and small navy.

Somewhat balancing the scales, however, was a secret weapon—Greek fire—not to mention Leo III the Isaurian, arguably the Byzantines’ greatest warrior-emperor. Recognizing the threat well in advance, the Byzantines had prepared by stockpiling food and supplies, and Leo used his diplomatic skills, and a great deal of Byzantine gold, to secure the aid of a large Bulgar army from outside Constantinople.

The defenders repulsed initial Mus lim attempts to take the city via the inlet known as the Golden Horn, as Byzantine light galleys called dromons (“runners”) rammed the Umayyad ships and set their decks ablaze with Greek fire—an early form of napalm that burned on water and could be extinguished only by sand or urine. Subsequent Mus lim incursions met similar fates.

Despite receiving reinforcements from Egypt and Africa, the Muslim army made no headway and finally lifted its yearlong siege after losing 22,000 men to the Bulgars at Adrianople.

Historians often credit Frankish commander Charles Martel’s celebrated victory at Tours in 752 with stopping the Muslim advance into Europe, but the force Martel faced—with far more troops at his command—was one-quarter the size of the army Leo had defeated. Leo’s victory is all the more notable in that it occurred when the Continent was in the throes of the Dark Ages and comprised mainly small, quarrelsome kingdoms that would have stood little chance of turning back the Muslim host.

The enemy of my enemy can be an ally. The Bulgars were never fast friends of the Byzantines, but a standing treaty coupled with Leo’s successful persuasion (and overt bribery) of their khan, Tervel—a fellow Christian who would fight for his faith—was decisive in breaking the siege.

Technology can give you an edge. The effective use of Greek fire enabled the Byzantines to neutralize the Umay- yad fleet as a fighting force.

Pick the right man for the job. Leo’s predecessor, Theodosius III, was more monk than commander and, indeed, ceded his throne to enter a monastery. Leo was by training and disposition a warrior whose organizational and tactical skills preserved Constantinople.

Plan ahead. The Byzantines had stored ample food and supplies for the siege, while the Muslims, unprepared for a harsh winter, died in droves from exposure, starvation and disease.

Know your strengths. Leo knew the double walls of Constantinople could withstand virtually any assault by land. Realizing the Muslims would rely on a seaborne attack, he concentrated on defending the Golden Horn with his nimble galleys spewing Greek fire.

Understand the consequences. Had the Muslims taken Constantinople in 717 instead of seven centuries later, Islam might have gobbled up Europe unopposed.

Siege of Constantinople (717–718)

The second Arab siege of Constantinople in 717–718 was a combined land and sea offensive by the Muslim Arabs of the Umayyad Caliphate against the capital city of the Byzantine Empire, Constantinople. The campaign marked the culmination of twenty years of attacks and progressive Arab occupation of the Byzantine borderlands, while Byzantine strength was sapped by prolonged internal turmoil. In 716, after years of preparations, the Arabs, led by Maslama ibn Abd al-Malik, invaded Byzantine Asia Minor. The Arabs initially hoped to exploit Byzantine civil strife and made common cause with the general Leo III the Isaurian, who had risen up against Emperor Theodosius III. Leo, however, tricked them and secured the Byzantine throne for himself.

After wintering in the western coastlands of Asia Minor, the Arab army crossed into Thrace in early summer 717 and built siege lines to blockade the city, which was protected by the massive Theodosian Walls. The Arab fleet, which accompanied the land army and was meant to complete the city's blockade by sea, was neutralized soon after its arrival by the Byzantine navy through the use of Greek fire. This allowed Constantinople to be resupplied by sea, while the Arab army was crippled by famine and disease during the unusually hard winter that followed. In spring 718, two Arab fleets sent as reinforcements were destroyed by the Byzantines after their Christian crews defected, and an additional army sent overland through Asia Minor was ambushed and defeated. Coupled with attacks by the Bulgars on their rear, the Arabs were forced to lift the siege on 15 August 718. On its return journey, the Arab fleet was almost completely destroyed by natural disasters and Byzantine attacks.

The siege's failure had wide-ranging repercussions. The rescue of Constantinople ensured the continued survival of Byzantium, while the Caliphate's strategic outlook was altered: although regular attacks on Byzantine territories continued, the goal of outright conquest was abandoned. Historians consider the siege to be one of history's most important battles, as its failure postponed the Muslim advance into Southeastern Europe for centuries.

Khan Tervel, the saint and savior of Europe

Following those circumstances in the beginning of the VIIth century, Bulgaria is under the rule of Khan Tervel. His reign continues for 21 years from 700 until 721. From the very beginning, he proves himself as a genius tactician and eliminates the Khazar Khanate, also expanding the borders of Bulgaria.

In the year 705, he was proclaimed Caeser, BY the Byzantium emperor Justinian II, for his aid in the organization of a coup in Constantinople to win back the throne that was Justinian’s by right. This was most unusual for that time since Caesar was a title given to the successor of the throne.

Khan Tervel as Saint Tribellius

With bravery and tactics will seal his name in the history of the Balkan Peninsula and Europe as the Khan who annihilated the Arab horde during the siege of Constantinople. For his deeds, the Bulgarian khan was also canonized as a saint from both the eastern Orthodox and also from the western Catholic churches, thus named St. Trivelius (or Tribellius) Theoktist the savior of Europe. The might of the Bulgarian Khan was remembered and glorified by European chroniclers up to the XVth century.

Second Arab Siege of Constantinople in 717–718

Byzantine: unknown. Commander: Emperor Leo the Isaurian.

Muslim: 210,000. Commander: Maslama.

Defeat of Muslim forces in their first serious attempt to overpower the Byzantine Empire led to another seven centuries of Christian power in southeastern Europe.

Historical Setting

Constantine the Great established the city of Constantinople as his capital in 323. In doing so, he occupied the former city of Byzantium, which for centuries had controlled the straits separating Asia and Europe. The Sea of Marmara is flanked northeast and southwest by the Bosphorus and the Dardanelles, two narrow straits linking the Mediterranean and the Black seas. Unless one goes completely around the Black Sea, the passage from Europe into Asia Minor is across one of those straits. Therefore, Byzantium/Constantinople/Istanbul has been an extremely strategic possession for both land and naval warfare, as well as overland and maritime trade. As Rome faded and Constantinople rose in power, it became the seat of the Eastern Roman, or Byzantine, Empire.

Muhammad the Prophet founded Islam in Arabia in the seventh century. Claiming his divinely inspired teachings, the Koran, to be the successor to the Bible and the fulfillment of God’s plan for humanity, he spread his faith by both proselytization and warfare. By coincidence (or divine intervention) Muhammad arrived on the scene just as the two Middle Eastern powers, Persia and the Byzantine Empire, had fought each other to an exhausted standstill. He was therefore able to acquire massive territorial gains hand in hand with the spread of his faith. Both Persians and Byzantines suffered major losses of real estate as well as major losses of converts to Islam, who found it less oppressive than the ultraconservative Orthodox Church.

Muhammad the Prophet had a public career of ten years (622–632), then died without publicly naming a successor. His close associate Abu Bakr was elected to succeed him but ruled only two years upon his death Omar reigned as caliph (“deputy”), the religious and political head of Islam. For ten years Omar oversaw Islam’s expansion into Byzantine territory, Persia, Syria, modern Iraq, and Egypt. It spread further still under the caliphate of Othman (644–656), ultimately stretching west to the Atlantic shore of North Africa as well as east to Armenia and Afghanistan. After he was assassinated Islam split into two major factions: the followers of Muhammad’s nephew Ali became the Shi’ites, while the supporters of the Syrian governor Muawiya started the Sunni faction. Muawiya established the Umayyad dynasty, which ruled from Damascus between 661 and 750.

Muawiya’s goal was the downfall of the Christian Byzantine Empire, for reportedly whoever was involved in capture of the capital city of Constantinople would have all his sins forgiven. Intermittently between 674 and 678 Muslim forces attempted to capture the city, by both land and sea, but the double walls protecting it proved too formidable. Muawiya settled for a peace treaty with the Byzantine emperor, which provided for an annual tribute from Damascus to Constantinople. For the next thirty years Muslim armies carried the faith as far as Spain and India, but the lure of Constantinople, the key to Europe, always beckoned. Caliph Walid (705–715) organized the forces necessary to seize the city, but died before the project began. Thus, his successor Suleiman sent men and ships to the Byzantine capital in 717.

The Byzantine Empire had suffered through a series of mediocre emperors since the last assault. Anastasius was now emperor. He came to the throne in 713 and was in the market for able soldiers to defend his realm. In his army served a general named Conon, better known as Leo the Isaurian. (He was probably from Syria rather than the Anatolian province of Isauria [modern Konia], however.) He had been a soldier since 705 and in 716 took command of the theme (district) of Anatolia. He harried the approaching Muslim army as it marched out of Syria toward Constantinople, then took the throne from Anastasius in March 717. Crowned Leo III, he immediately set about laying in as many provisions as he could for the siege he knew was coming, a daunting task for a city of perhaps half a million people. He also oversaw the repair and strengthening of the city’s two walls and the placement of weaponry to repel attacks from land or sea.

Caliph Suleiman named Muslama as commander of his army, reportedly 80,000 men marching through Anatolia toward Constantinople. His plan was to invest the city from the western, landward side while a huge fleet blocked any supplies from reaching the city. That fleet numbered some 1,800 ships carrying a further 80,000 men under the command of a general named Suleiman, not to be confused with the caliph. The Muslim fleet was divided into two divisions: one to blockade the Dardanelles (or Hellespont) and keep any relief from coming to Constantinople from the Mediterranean, and one to hold the Bosphorus to the north, keeping out any relief from Black Sea ports. Muslama crossed the Hellespont in July 717, then divided his forces. He took command of the main body that began the siege, while sending a detachment to Adrianople to keep an eye on the Bulgars, who had been pillaging through southeastern Europe and had attacked Constantinople in 712.

Immediately upon his arrival Muslama threw an attack against the walls, but it was easily beaten back. That convinced him against undertaking a frontal assault, so he began digging trenches to prevent any breakout from the city. Most of the fighting, therefore, took place on the water. Admiral Suleiman left part of his navy at the Dardanelles, as ordered, but led the remainder northward to take up station on the Hellespont. As they approached Constantinople, however, the leading ships were caught in a swift and unfamiliar current that began to tangle them. Seizing his opportunity, Leo quickly lowered the chain that protected the Golden Horn (the upper harbor of the city) and dashed out into the Muslim fleet before they could form into line of battle. Using Greek fire, his ships quickly destroyed or captured a large number of vessels while the rest retreated. Suleiman feared sailing past the city now, for another such battle could destroy the rest of his fleet. Thus, the northern avenue for aid for a time was kept open.

The Muslim effort was off to a poor start, and soon bad news came from Damascus. Caliph Suleiman had died of a stomach ailment (probably from overeating) and Omar II, not known for his military acumen, had replaced him. For the next several months little happened except for bad luck. The winter of 717–718 was much colder than usual and snow lay on the ground for more than three months. For an army born and raised in Arabia and Egypt this was disconcerting at best, deadly at worst. Delays in the delivery of supplies from Egypt, coupled with the bad weather, meant the deaths of thousands of besieging soldiers.

The Muslims hoped to take the initiative in the spring of 718 with the arrival of a new fleet from Egypt bringing 50,000 reinforcements. The 400 ships of the fleet from Egypt slipped past the Byzantine fleet in the Golden Horn at night, thus avoiding a naval battle, and anchored at the Hellespont. That cut off the flow of supplies and would eventually have spelled the city’s doom, but Leo’s navy again saved the day. He was aided by the desertion of large numbers of crew members from the new Egyptian fleet, sailors who were Coptic Christians and had been pressed into Muslim service. Learning of the enemy fleet’s disposition, Leo launched a surprise attack in June that caught them completely unawares. The Greek fire (an unknown mixture of materials with many of the characteristics of napalm) once again caused both destruction and terror the Christian crews deserted wholesale to the welcoming Byzantine forces. The northern blockading fleet was destroyed and Leo followed up his victory with an attack on Muslim forces on the Asian side of the Sea of Marmara, opposite the capital. That attack was so unexpected that Muslim soldiers and sailors were slaughtered by the thousands.

Leo at this point proved himself to be a diplomat as well as a general. He sent envoys to the Bulgars, who persuaded their King Tervel to attack the Muslim army from the west. In July Tervel’s soldiers drove back the Muslim holding force at Adrianople and attacked Muslama’s forces in the rear, defeating them and inflicting some 22,000 casualties. This new threat was reinforced by the rumor that a Frankish army was marching across Europe to assist their fellow Christians. The Muslims had not yet fought the Franks, but had heard tales of formidable military power. Caliph Omar decided it was time to bring the siege to a close. On 15 August 718 Muslama led the army away from Constantinople.

The defeat at Constantinople was the first disastrous loss the armies of Islam had suffered. There had been occasional defeats, but never a catastrophe such as this. Of the 210,000 Muslim soldiers and sailors who took part, it is reported that only 30,000 actually saw their homeland again. Of the more than 2,000 ships reported to have been involved, only five supposedly made it home.

Had Muslama’s armies captured the city, the route into eastern Europe would have been virtually unguarded. Little organized resistance could have been mounted against hordes of Muslim troops until they reached central Europe. Constantinople, the seat of political, religious, and economic power in the Christian East, probably would have become Islam’s capital as it did in the wake of the Muslim capture of the city in 1453. The Eastern Orthodox Church may have disappeared, with untold consequences in eastern Europe and Russia, although such did not happen in 1453. Sea power would have been completely in Muslim hands, for no European population at the time owned a significant navy. None would until the Vikings a century later. Even with the Frankish victory at Tours in France fifteen years afterward, Islam could well have become the dominant European, and therefore world, religion.

The Byzantine victory insulated Europe from Islam, but also from other outside influences. Hellenistic knowledge and culture survived and in many ways flourished in the Middle East and Africa, while Europe entered the Dark Ages. Militarily Europe was strong, but cultural progress was at a crawl. Not until the Crusades and the resulting revival of trade with the East was the old knowledge rediscovered, and the Renaissance was the result. It is interesting to speculate what Europe may have been like had Constantinople fallen seven centuries before it did.

References: J. F. C. Fuller, Military History of the Western World, vol. 1 (New York: Funk and Wagnalls, 1954) Edward Gibbon, The History of the Decline and Fall of the Roman Empire, vol. 6 (London: Methuen, 1898) Warren T. Treadgold, Byzantium and its Army, 284–1081 (Stanford: Stanford University Press, 1991).

Watch the video: April 6, Friday - Fall of Constantinople in 1453 part1 (December 2021).