Constantinople: The History and Importance of the Capital of the Eastern Roman Empire

Constantinople was the largest and wealthiest city of the Middle Ages and one of the few remnants of the once all-encompassing Roman Empire. It ruled the Golden Horn, a natural estuary connected to the Bosphorus Strait in modern Turkey, where it thrived on trade.

Early History of Byzantium and Constantinople

Byzantium – the future Constantinople – was originally a Greek settlement founded in the seventh century BCE. In ancient Greek, it was known as Βυζάντιον (Byzantion). Popular legends point to a Megarian king by the name of Byzas as the city’s founder. Of course, in Classical Greek fashion, Byzas was either the grandson of Io or the offspring of a nymph by the name of Semystra. Nope, no one could ever be just “some guy,” and especially not the founder of a city as spectacular as Byzantium.

For years Byzantium was a famous trade city thanks to its prime geographic location. The Byzantine Territory was a coveted jewel for its ease of access to the Black Sea and coastal Asiatic trade routes.

The Scythian Campaign of Darius I saw that Byzantium became part of the Achaemenid Empire, which gave the Achaemenids control of several valuable ports. This was around 513 BCE, and by 411 BCE the Spartans came knocking during the Peloponnesian War. Let’s just say a lot was happening in the Mediterranean as Sparta and Athens warred. In 408 BCE, the Athenians seized control of the ancient city and the Greeks held its control.

READ MORE: Ancient Cities: Pompeii, Rome, Teotihuacan, Palmyra, and More!

That is, the Greeks were totally in control until they gave favor to a certain Roman usurper during the Year of the Five Emperors in 193 CE. Times were crazy when the new emperor Septimus Severus rolled up with his Legions and caused a massive amount of damage to the city. It turns out ancient Rome didn’t believe in slaps on the wrist, and certainly not for such treasonous offenses. Severus rebuilt the city once he determined that the Byzantines learned their lesson and once he realized their vital placement in the region dubbed the Golden Horn.

Founding by Constantine (284 – 337 CE)

It all begins with the Roman emperor Constantine I who just really loved the city. He renamed it Nova Roma (New Rome) upon seeing the potential of an expanded city and established it as the main imperial residence in 324 CE. The great city was highly defensible, rich in trade, and wasn’t far from Roman Asia or the frontiers stretching along the Euphrates and Danube rivers. Emperors could take quick, decisive actions with little risk.

READ MORE: Roman Emperors in Order: The Complete List from Caesar to the Fall of Rome

Only later, around 330 CE, was Nova Roma given the name Constantinople in honor of Constantine I. Under his influence, Constantinople became a Christian city and the epicenter of Greek and Roman art. Remnants of The Great Palace of Constantinople, Constantine’s imperial palace, remain visible in modern Istanbul.

READ MORE: Ancient Greek Art: All Forms and Styles of Art in Ancient Greece

The Importance of Constantinople

Constantinople was the base of the Eastern Roman Empire and acted as the imperial capital from the time of Emperor Constantine I. It was, effectively (and literally), “New Rome” during the over a thousand years of the Byzantine Empire (330 CE – 1453 CE). Most notably, it was a cultural melting pot and the center of art and Christianity in the Middle Ages.


Constantinople was by and large Hellenic. It was, after all, a Greek city before the Persians and Romans. After it became the Byzantine capital in 330 CE, Constantinople remained primarily Greek-speaking. It became the center of the Orthodox Christian church, with Christianity as the city’s – and Empire’s – official religion.

Both the culture and language of Constantinople were Greek despite its declaration as New Rome. It remained such until the Fall of Constantinople at the hands of the Ottoman Turks.


As the capital of the Byzantine Empire, Constantinople was led by the reigning emperor. Over the course of its history, there were 93 Byzantine emperors and just about all ruled from Constantinople in the Great Palace.

The government of Constantinople has been described by scholars as a “monarchic theocracy.” In short, religion (in this case, Christianity) ran the government and thus all aspects of politics and society were justified by and related to the official religion. The emperor was seen as the “Vicar of Christ,” a representative of God on Earth.

Alternatives suggest that Constantinople was a Caesaropapist state, where the emperor was the head of church and state. Religious authorities were then subordinate to the emperor; the emperor had a complete mandate over the ecclesiastical hierarchy and its structure. A prime example of this is that the Archbishop of Constantinople was not able to hold his seat if the emperor disapproved of him.

There were other government officials and viceroys who were granted the same almighty power as the emperor in their respective regions. However, at the end of the day, everyone – from priests to paupers – had to obey the Byzantine emperor.


The architecture of the Byzantine Empire, specifically in Constantinople, is extremely Roman. At least in this aspect, they were quite accurate to call it Nova Roma. Iconic features of the city, such as the Hagia Sophia, are reminiscent of Early Christian designs. Otherwise, Greco-Roman architecture was the standard.

The city walls are among the most famous features of the ancient city. They still stand to this day, known as the Walls of Istanbul, and date back to the city’s founding by Constantine I. In antiquity, the series of limestone walls gave credence to the claim that Constantinople was the most fortified city in the Eastern Empire.


Orthodox Christianity was the major, official religion of Constantinople. As we previously addressed, the politics of the Byzantine capital were heavily entwined with its official religion. One of Constantine’s first orders of business was building a church dedicated to Jesus’ 12 Apostles. Thus, the Church of the Holy Apostles was erected. Many other churches quickly followed suit, including the Church of the Holy Wisdom, the Hagia Sophia in 537 CE.

The Roman emperor Constantine’s most significant contribution to the religion of the Byzantine Empire is the phenomenon of the Constantinian Shift he helmed. He pushed for the decriminalization of Christianity and put an end to the persecution of Christians during his reign. It is no shock to anyone, then, that Constantinople was considered a holy city by the fifth century CE.

Constantinople as the Christian Capital

By the Middle Ages, Constantinople was considered the Christian capital. Whereas Rome was the center of Catholicism and filled with Roman Catholic churches, Constantinople became famous as the seat of Eastern Orthodox Christianity. The great city remained the Christian capital until it fell to the Ottomans in 1453.

Constantius to Theodosius (337 – 526 CE)

The early years of Constantinople were among its most important. Although Constantine the Great laid the city’s foundations, it was his son, Constantius II, and the emperors thereafter that made it into the splendor that we know so well today.

Constantius II saw a reign strife with warfare and serious political unrest. Not only did the new Eastern Empire have beef with the Sassanid Empire, but there were continued blows exchanged with the Germanic peoples to the north. Adding in the fact that Roman politics were absolutely brutal and everyone wanted to usurp the reigning emperor at any given time.

With surprising success (and brutality) Constantius II was able to consolidate power within the Constantinian dynasty. This came after several purges of his kinfolk and defeating a usurper, Magnentius. He was preparing to fight his young cousin, Julian the Philosopher, for the throne when he died. Despite their tense relationship, Constantius II named Julian his successor in 361 CE.

Of course, Julian died after biting off more than he could chew when he attempted to campaign against the Sassanid Empire. After being mortally wounded in 363 CE, he named an imperial bodyguard, Jovian, as his successor. Jovian lasts literally less than a year as Augustus Caesar and the throne of ancient Rome becomes split between two brothers: Valentinian I in the West and Valens in the East.

Valens (364 – 378 CE)

With control over the Eastern Roman Empire, Valens was in constant conflict with the Goths of the region. He also struggled with the Persians, but that was pretty standard in the Eastern provinces. After the Gothic War (376 – 382 CE) broke out, Valens died in the Battle of Adrianople in 378 CE. During his reign, he finished the Aqueduct of Valens in Constantinople, an aqueduct that was originally started by Constatius II.

Theodosius I (379 – 395 CE)

The successor of Valens, Theodosius I was officially the last Roman emperor to rule over a united Rome. After his rule, emperors held distinct administrations between the West and East.

Theodosius I most famously helped establish the Creed of Constantinople (alternatively, the Nicene Creed) with the First Council of Constantinople in 381 CE. Though this was in direct opposition to Arian Christianity, the bishops of the First Council determined the Nicene Creed to be orthodox. Arianism was the faith of former emperors Constantius II and Valens, despite Constantine I holding the First Council of Nicaea and drafting the original Nicene Creed.

Arcadius (395 – 408 CE)

The story of Constantinople as an independent entity begins during the reign of co-emperors Arcadius (378 – 408 CE) and Honorius (385 – 423 CE), under whom the two parts of the Roman empire finally went their own ways. Arcadius succeeded his father Theodosius I in Constantinople as the Eastern emperor in 395 CE. He was only 17 years old, and unfortunately, both he and his younger brother, the Western emperor Honorius, were naive and inexperienced.

Throughout Arcadius’ reign, his ambitious wife, Aelia Eudoxia, held much influence over court affairs and political schemes. He also relied heavily on older, power-hungry ministers within his government for guidance, such as the Eastern praetorian prefect, Flavius Rufinus, and eunuch-turned-consul, Eutropius. Meddling from court officials led to a schism between the East and West that lasted until Arcadius’ death. Meanwhile, Eudoxia came into constant conflict with the immensely popular Patriarch of Constantinople, John Chrysostom.

Theodosius II (408 – 450 CE)

When Arcadius died in 408 CE, he was succeeded by his seven-year-old son Theodosius II. Granted that there was a literal child on the throne in Constantinople (again), the new administration was weak. As a consequence, the Visigoths were able to sack Rome, and the West was left vulnerable to invasions at the hands of the Goths and Alans without Eastern support.

Most of Theodosius II’s early reign saw that the empire was controlled by the praetorian prefect of the East, Anthemius, and the state apparatus. Under Anthemius, Constantinople’s Theodosian Walls were constructed as a direct response to the 410 CE sacking of Rome. Peace was also brokered with Persia, leading to wary diplomatic relations between the empires.

414 CE saw Theodosius II’s older sister Pulcheria, then only fifteen, become the young emperor’s official guardian. She was notoriously pious, having wholly dedicated herself to the Christian faith and taking an oath of chastity. She eventually became the wife of Marcian, without ever breaking her oath. Once of age, Theodosius was proclaimed sole emperor though he still relied on his elders – and his sister – for guidance.

Besides the accomplishment of the Theodosian Walls, Theodosius II’s reign also saw the adoption of the Codex Theodosianus into Roman law in 439 CE. Alongside Valentinian III of the Western Empire, Theodosius II successfully codified the laws of the Roman Empire from 312 – 438 CE. Within the Codex were Theodosius II’s attempts to unify Christianity and reinforce it as the Roman Empire’s official religion.

Under constant pressure from the Huns and their co-rulers, Attila and Bleda, Constantinople signed the 435 CE Treaty of Margus. Thus, the Eastern Roman Empire was forced to pay tribute to the ever-expanding Huns. After a Roman breach of the treaty and years of back and forth, the Peace of Anatolius was signed; Attila continued raids throughout the Eastern Empire and its territories had to pay double the previous tribute.

Marcian (450 – 457 CE)

Marcian was Theodosius II’s successor, though he was an unrelated assistant to imperial commanders. Pulcheria consented to go through with the marriage to bring Marcian into the imperial family circle and justify his succession.

READ MORE: Roman Marriage

Marcian’s brief reign was distinguished by his rejection of the Hun tribute. Marcian would likely have faced the consequences of this if it wasn’t for Attila’s focus on obtaining territory in the Western Empire. Moreover, Attila’s Western ambitions left the Hungarian Plain open for invasion, which Marcian more than happily took advantage of.

In his seven short years of being emperor, Marcian also made religious revisions to Theodosius II’s previous laws. He hosted the Council of Chalcedon, whose conclusion that Jesus had a dual nature left several of the Eastern provinces alienated on account of their miaphysitism.

Leo the Great (457 – 474 CE)

The successor to Marcian, Leo the Great was determined to be emperor on the word of renowned commander and minister, Aspar. In 467 CE Leo appointed Anthemius to the vacant position of emperor of the West.
Then, in a rare display, the East and West united their forces to crush the Vandals and Alans in the Mediterranean.

Unfortunately, the imperial fleet, commanded by Leo the Great’s brother-in-law Basiliscus, was destroyed by the King of the Alans and Vandals, Gaiseric, in 468 CE. The failed expedition had a drastic effect on the imperial treasury.

Leo II (473 – 474 CE)

With Leo dead, the rule of Constantinople fell to his boy grandson, whom he had made co-emperor in 473 CE. Leo’s son-in-law Zeno, the father of Leo II, was to be regent during the boy’s childhood. But, Zeno was brutally ambitious. In February 474 CE, Zeno fashioned himself as co-emperor, and within the year Leo II was dead.

Conspiracies abound, no one quite knows the cause of the boy emperor’s death. From poison to natural causes, the mystery surrounding Leo II’s demise only increased his father’s – and successor’s – unpopularity.

Zeno (474 – 475 CE)

Born as Tarasis in Isauria (modern-day Turkey), he changed his name to Zeno to gain acceptance within the Greek-speaking empire. Zeno was eventually married to the daughter of Leo the Great, Ariadne, after the death of his first wife, Arcadia. He co-ruled with his young son, Leo II, until the child’s untimely death.

Despite Zeno’s success in making peace with Gaiseric, the Vandal King, he was terribly unpopular. The people of Constantinople hated him for his Isaurian origins and, thus, Zeno’s reign as sole emperor was cut short. He was unceremoniously ejected from Constantinople by the very Basiliscus whose fleet under the rule of Leo the Great had been annihilated.

Basiliscus (475 – 476 CE)

Basiliscus kicked Zeno out of town and snatched the throne for himself with the aid of Teutonic mercenaries. He allowed angry mobs to kill Isaurians in Constantinople and put to death a handful of his co-conspirators who helped overthrow Zeno. As if that wasn’t enough, he raised taxes and made himself an enemy of the church.

Basiliscus, too, didn’t last long, falling from power in 476 CE as Zeno marched on the city. The Senate welcomed the former emperor back with open arms.

Zeno – again (476 – 491 CE)

Well, Zeno was back. Not necessarily by popular demand, but he was back.

In 477 CE, envoys arrived in Constantinople. Odoacer, the Germanic conqueror of Rome, would voluntarily submit to him. The only catch was that he would be allowed to remain King of Italy on Zeno’s behalf. So yeah, that peace treaty was a steal.

As before, no matter how well Zeno was performing as emperor, people found fault with it. Theodoric Strabo – one of Basiliscus’ conspirators – specifically took issue with Zeno since he refused to make him head of the army. He petitioned the aid of Theodoric the Amal, King of the Ostrogoths, as retribution. Long story short, Strabo was bribed to betray the Amal, the war between the Ostrogoths and Constantinople lasted four years, and Strabo eventually died anyway by…falling onto a spear.

Afterward, Theodoric the Amal entered into a peace with Zeno. He was granted military prestige, wealth, and land. The Amal helped shut down Illus’ revolt and the attempted usurper Leonitus, who turned Odoacer against Zeno. By the time Zeno had died in 491 CE, the Balkans were naught but a war-ravaged landscape and Constantinople was strife with religious tension. After the failure of the Henotikon in 482 CE, the Acacian schism between the Western and Eastern Christian churches was officially underway.

Anastasius I (491 – 518 CE)

So, Zeno left no apparent heir. This time, Zeno’s widow, Ariadne, hand-selected the civil servant Anastasius. Thanks to someone who actually sort of knew what they were doing at the helm of the Byzantine Empire, Anastasius I’s reign was marked by major governmental reforms as well as economic and bureaucratic reforms.

With newfound economic stability and a sizable treasury, Anastasius I was able to leave Constantinople exceedingly prosperous. But, womp womp, religion wasn’t doing too hot. The new emperor was a miaphysite and replaced the Metropolitan of Chalcedon with an ecclesiastically like-minded man in 512 CE. Riots erupted, and a general by the name of Vitalian started a rebellion.

The rebellion put fire to Anastasius’ feet and he agreed to open talks with the Pope in Rome to put an end to the Acacian schism. Vitalian’s rebellion was short-lived.

Justin I (518 – 527 CE)

This next emperor was a retired Thracian soldier named Justin. He was elderly and didn’t change much from Anastasius I’s reign. Justin’s most notable achievement was officially ending the Acacian schism and leaving the Byzantine Empire in good standing with the papacy. His rule is also the start of the infamous Justinian dynasty.

Justinian and the Nika Revolt (527 – 565 CE)

Justinian I was Justin I’s nephew and – for a handful of months – his co-ruler. Though Justinian scandalized polite society after marrying a performer, Theodora, his early rule was a prosperous one. He was fantastically educated and a tactful politician.

By 528 CE, Justinian was forced into a full-out war with Persia after the revival of the Sassanid dynasty. Kavad I, the Sasanian King of Kings, had claimed his son, Khosrow, as his rightful heir. For some reason, the Byzantines didn’t like that; it probably had something to do with continued territorial disputes over the kingdom of Lazica.

The following Iberian War would technically last two years since there was no direct confrontation until 530 CE. Once Kavad I died the next year, his son and successor was willing to make peace. For the imperial courts, peace couldn’t come soon enough. In 532 CE, the Nika Revolt was in full swing.

For background, the Nika Revolt was a long time coming. For all his political savvy, Justinian had a habit of choosing unpopular officials. The riots began between two rival chariot racing groups, the ‘Blues’ and the ‘Greens’, in the Hippodrome. As these things tend to go, they rapidly spiral into a full-scale revolt against Justinian I’s authority.

The revolt was, with difficulty, quelled. Historians estimate that over 30,000 unarmed civilians were slain and riot instigators – nephews of the former emperor Anastasius I – executed. The Nika Revolt destroyed nearly half of Constantinople. The extensive damage enabled Justinian to exploit his own hobby of building. Thus came about extensive rebuilding and new architecture, such as the celebrated Hagia Sophia.

Throughout the rest of Justinian’s reign, he managed to crush the Vandal Kingdom in North Africa, wrestle Rome from the Goths (though they would remain a thorn in his side), and war with Persia two more times. This was all while staying faithful to Theodora, who was openly sympathetic to the miaphysite cause, and upholding Roman law. His glorious reign, however, was wracked by war, which left the imperial coffers all but strained. 

Medieval Constantinople (until 1453 CE)

“Constantinople was by its situation the center and seat of universal domination.” 

(The Memorial of Saint Helena, 1823)

The Middle Ages began in 476 CE with the fall of the Western Roman Empire. The emperor of the Western Roman Empire Romulus Augustulus was exiled by the Germanic king Odoacer and henceforth, no Roman emperor ever ruled from Italy again. Instead, the Christian city of Constantinople was the last vestige of imperial authority in Western Europe. With a firm central government, medieval Constantinople began to see a period of opulence – but not peace.

The medieval era of Constantinople saw further conflict with old enemies and new ones. With the presence of the Persians on their borders of Asia Minor and threats from the Normans and Franks, Constantinople found conflict around every corner. That is to also mention that the Western Roman Empire was back but rebranded as the Holy Roman Empire in 800 CE. Yeah, the Byzantines weren’t sure how to feel about that.

During Constantinople’s medieval height, they were no stranger to religious discord, either. There was the Schism of 1054 which caused extended tension between the Catholic and Eastern Orthodox Christian church. Despite its ups and downs, Constantinople maintained its title as the “Cradle of Orthodox Christian Civilization” across its 1,100-year history and well into the medieval era.

As far as economics goes, fabulous wealth from Western Asia flowed with ease into Constantinople through its ports. The Golden Horn was the focal point for trade, offering coastal protection for ships passing through its waters. The Middle Ages were one of the Byzantine Empire’s highest points historically, and for most of the medieval era, it was the wealthiest European city. That is, until the Fourth Crusade in 1203.

The Fourth Crusade saw the Siege of Constantinople of 1203 that established the prince Alexios IV Angelos as co-ruler of the Byzantine Empire. What’s crazy is that the Crusader army wasn’t even supposed to be anywhere near Constantinople – they were sent by Pope Innocent III to reclaim Jerusalem! They were promised high payment by Alexios Angelos and, well, were momentarily excommunicated by the papacy anyway.

When Alexios was murdered and the army wasn’t paid they thought, “Hm, why not totally conquer the city?” Constantinople’s wealth was plundered and the Byzantine Empire was fractured into three states: the Nicene Empire, the Trapezuntine Empire, and the Despotate of Epirus. Then the Crusaders established the Latin Empire (1204 – 1261) with the administrative center on – guess where – Constantinople.

Fall of Constantinople

The Fall of Constantinople occurred on May 29, 1453, at the hands of Mehmed II, the sultan of the Ottoman Empire stylized as “ the Conqueror.” At the time, the ruler of the Byzantine Empire was Emperor Constantine XI Palaiologos. He had only been in power for 4 years.

The fall of the Byzantine Empire came after a 53-day Arab siege, in which the expansive Ottoman army encircled the wealthy city by land and sea. After continued cannonfire bombardment, the Ottomans were able to breach the Theodosian walls of the city. When all was said and done, the once great city was thoroughly sacked of its riches; Mehmed II gave his men 3 days to plunder. The literary treasures of the city were dispersed or destroyed, and 60,000 of the population were sold into slavery. The once beautifully constructed imperial palace lay abandoned and in ruins.

Alas, with the Arab siege, the eminent city fell. Along with its demise, the Eastern Roman Empire fell, too. The epic rise and fall of Constantinople left an inalienable mark on Western Europe – and the rest of the world, for that matter.

European Response to the Fall of Constantinople

Since its inception the city of Constantinople was a Christian city. The fall of Constantinople at the hands of Ottoman Turks caused widespread panic among other Christian kingdoms. The assumption was, that if the imperial armies failed to defend the Byzantine capital against the Muslim Ottoman Empire, then what was to become of everyone else? The military failures of Emperor Constantine XI aside, Europe was stressed.

Given Constantinople’s geographical location, the city was the first line of defense against Ottoman invasion extending into and past the Eastern Mediterranean. As far as history tells us, the Ottoman Sultan Mehmed II was certainly determined to expand his empire’s influence. He went on to conquer the Despotate of Morea and swathes of Anatolia that were under the rule of the Trapezuntine Empire, along with other key regions.

People began to wonder the best approach to the new political landscape. Some folks called for another Crusade to chase off the Ottomans. Others called for diplomatic discussions.

Constantinople’s defeat – more than anything – caused serious damage to European trade. Italian city-states, such as Venice and Genoa, relied on Constantinople for more than just defense, but also for economic stimulation. Politics shifted dramatically across Europe as rulers attempted to cope with the losses wrought by Constantinople’s fall.

Such consequences coincidentally led to some nations seeking alternative routes to Asia Minor and the Far East so as to avoid going through the Ottoman Empire. They didn’t want to pay an exorbitant tax, which they were confident Mehmed II would enforce. Thus, the Age of Discovery became rapidly underway.

Ottoman Rule

Under Ottoman rule, Constantinople became an Islamic city. The Hagia Sophia was transformed into a mosque. However, the Ecumenical Patriarchate of Constantinople remained intact per Mehmed II’s demands; a Greek scholar, Gennadius II, was arranged as Patriarch.

Based on an eyewitness account from the Byzantine historian George Sphrantzes, Mehmed II proclaimed on the third day after Constantinople’s defeat. According to such a decree, civilians who survived the siege were encouraged to reveal themselves on the promise of freedom and a return to normalcy. They could continue to own their property and practice their own faith. Unfortunately in the siege, many homes were ransacked or destroyed and churches, such as the Hagia Sophia, were centers of bloody violence during the conflict.

Life was never quite the same in Constantinople after it came under Ottoman rule. Though the city did flourish as the new capital of the Ottoman Empire, future generations dreamily looked to the old days of what was once the untouchable Eastern Roman Empire. The Ottomans remained in control of Constantinople until its official dissolution in 1922.

Constantinople Becomes Istanbul, the Capital of Turkey

Constantinople became officially known as Istanbul on March 28, 1930. Constantinople was still the capital of the Ottoman Empire until its dissolution in 1922. The Republic of Turkey simply changed the name of the old (new) capital. The switch-up wasn’t sudden, since many people within the city were already referring to it as Istanbul.

Up until its official renaming to Istanbul in 1930, Constantinople was known in Turkish as Konstantiniyye (قسطنطينيه‎) in official documents. And, during this period, Constantinople wasn’t the only city within the Republic of Turkey to go through a name change. The Turkish standardization of various cities throughout the former Ottoman Empire was an intentional effort throughout the 20th century.


The Sack of Constantinople

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