Constantinople: History of the Byzantine Capital
Three names for one city with a prestigious destiny. Embark on a journey to explore the ancient wonders of Constantinople, a city with a unique and fascinating history. From the Greek city of Byzantium to the opulent medieval Constantinople, before it became Istanbul, experience the tumultuous history of a city that has fascinated the world for more than a millennium.
If you plan to visit Istanbul and discover its Byzantine monuments, check our Visitor Guide.
Byzantium, a Greek city with a significant role.
In the first half of the 7th century BCE, Doric Greek colonists, likely from Megara, founded a new city on the European coast of the Bosphorus Strait. It was named Byzantium after a legendary figure, Byzas. While the site had been occupied long before this event, it marked Byzantium’s entry into history.
Its privileged position on the Bosphorus ensured significant prosperity. It could control the traffic of ships carrying wheat from the Pontus Euxinus (the ancient name for the Black Sea) to the Mediterranean and became one of the foremost ports in the Greek world. This advantageous situation led to Athens and Sparta vying for alliance with Byzantium, and to rulers seeking to conquer Greece wanting to control it.
Though details of its history are scant, its political role was significant, and it was a focal point in many conflicts: it was taken twice on behalf of the Persians during the Persian Wars, before the Spartan Pausanias took it after 478 BCE. Subsequently, Byzantium fell under Athenian influence. Revolting against them along with Samos, it was subdued by a siege in 439 BCE. Then, during the Peloponnesian War between Athens and Sparta, it was subject to one camp or the other depending on the vicissitudes of the conflict.
Returning under Athenian domination, it finally gained independence in 364 BCE. But Philip II of Macedonia attempted to seize it in 340 BCE. He failed due to the intervention of an Athenian general. However, under the reign of Alexander the Great, Byzantium was forced to recognize Macedonian suzerainty. It regained its independence under his successors but faced invasion by the Gauls in 279 BCE and conflict with Rhodes, a major power at the time.
Ultimately, Byzantium fell under Roman control.
Constantinople, the New Rome, and the Byzantine era.
Its destiny radically changed in 330 CE when Constantine decided to establish his capital there. The city, refounded as Constantinople, became the New Rome. Endowed with monuments befitting a capital, the city became for a millennium the heart of the Byzantine Empire, a major center of Christianity, and one of the greatest cities of its time. Its formidable fortifications, hundreds of churches including Hagia Sophia and the Church of the Holy Apostles, sumptuous palaces, civic monuments, and flourishing industries ensured it a unique prestige and radiance.
But the city was not spared vicissitudes: revolts, earthquakes, sieges, and fires transformed it over the centuries, following or marking the tumultuous history of the Byzantine Empire. In 1203-1204, the diversion of the Fourth Crusade and the foundation of a brief Latin Empire constituted a rupture from which the Byzantine Empire, even though it reclaimed Constantinople, never fully recovered. The following two centuries, under the Palaiologos dynasty, were culturally brilliant but saw the empire gradually decline, both under external pressures and due to civil wars, internal conflicts, and the impact of the Black Death.
The journey to Istanbul, capital of the Ottomans and of modern Turkey
In 1453, Mehmed II conquered the city and made it the capital of the Ottoman Empire. The city entered its third age and, from an ancient Christian and medieval city, became a Turkish and Muslim metropolis dominating a vast empire. Constantinople – or according to its Turkish name, Istanbul, which became the sole usage from 1930 – was profoundly remodeled over the following centuries. Traditional Byzantine centers of power were abandoned in favor of the Topkapi Palace. The sultans covered the city with numerous monuments, many churches were converted into mosques or destroyed to build other monuments. Earthquakes and modernity also took their toll. In 1871, a railway line was built to the heart of the historic city, cutting through the remains of many Byzantine monuments: part of the maritime walls, the Bucoleon Palace, or the Mangana Palace were thus destroyed.
Three snapshots of a city in mutation
The Theodosian City: Constantinople as the New Rome (330–453)
When Constantine chose the ancient Greek city of Byzantium as the site of his new capital in 324, the choice was strategic but the ambition was ideological. The city he founded in 330 was not merely a new administrative center — it was a deliberate reinvention of Rome itself, transplanted to the Bosphorus. Constantinople was laid out on seven hills, like Rome. It received a Senate, a new Forum centered on a towering porphyry column bearing Constantine’s own image, and a Hippodrome directly adjoining the imperial palace — a conscious echo of the Circus Maximus beside the Palatine. The great ceremonial avenue, the Mese, served as a new Via Sacra, lined with statues looted from the sanctuaries of the ancient world. From its very first stones, Constantinople was designed as a transfer of Roman legitimacy to the East.
Constantine’s city was also, from the outset, a Christian one. He began construction of the first Hagia Sophia and the Church of the Holy Apostles — intended as his own mausoleum — establishing the sacred poles that would define the city’s religious geography for centuries. The imperial palace, the Hippodrome, and the nascent cathedral formed an integrated precinct of power and ceremony that would remain the heart of Constantinople throughout its existence. The harbors on the Golden Horn to the north and on the Propontis to the south were developed to supply a city growing faster than any other in the Roman world.
The work of Constantine’s successors deepened and extended this urban vision. Under Theodosius I, new forums multiplied along the Mese — the Forum of Theodosius, dominated by a triumphal column, became the grandest public space in the city. The Obelisk of Theodosius, erected in the Hippodrome in 390, still stands today. The aqueduct of Valens, completed in the 370s, brought water from Thrace to feed the cisterns that would sustain the city through sieges and droughts alike — an infrastructure as essential to Constantinople’s survival as its walls.
Those walls came under Theodosius II. In 413, the young emperor’s praetorian prefect Anthemius oversaw the construction of the great land walls that still define Istanbul’s western horizon — a triple line of walls, towers, and moats stretching from the Golden Horn to the Propontis. Extended in 439 with new sea walls completing the city’s defensive perimeter, the Theodosian walls fixed Constantinople’s maximum extent for the remaining thousand years of its existence. Inside them, Theodosius II founded the first institution of higher learning in the city in 425, drawing scholars and administrators that cemented Constantinople’s role as the intellectual capital of the Roman world.
The dynasty’s final contribution came from Pulcheria, sister of Theodosius II and the most powerful woman in 5th-century Byzantium. Her church foundations completed the sacred geography of the city in ways that would resonate for centuries. The church of the Theotokos at Blachernae, built on the northwestern edge of the city near the walls, enshrined a relic of the Virgin’s robe and established Constantinople as a city under Mary’s direct protection — a theological identity that would shape how Byzantines understood their capital through every subsequent siege and crisis. Her church of the Virgin at Chalkoprateia, near Hagia Sophia, added another Marian pole to the city’s devotional landscape.
By the time Pulcheria died in 453, Constantinople had been transformed from a hastily founded capital into one of the great cities of the world — with perhaps 300,000 to 400,000 inhabitants, a fixed urban skeleton of walls, harbors, aqueducts, forums, and churches that no subsequent ruler would fundamentally alter, only build upon. Within two decades, the Western Empire had collapsed. Constantinople stood alone as the heir of Rome.
Justinian’s Constantinople: A city remade (527–565)
The Constantinople that Justinian inherited in 527 was no longer the raw, expanding capital of Constantine’s day, nor quite the city of Pulcheria. In the three-quarters of a century since the Theodosian dynasty closed, its outer shape had scarcely changed — the land walls still fixed its limits, the aqueducts still fed its cisterns — but within that frame the city had filled, hardened, and grown restless. Under the Leonid emperors and above all under Anastasius I (491–518), Constantinople had become an administrative machine of formidable efficiency. Anastasius reformed the coinage, abolished the hated chrysargyron tax, and left in the treasury a famous surplus of some 320,000 pounds of gold — the war chest that would, in time, pay for Justinian’s wars and his buildings alike. Beyond the land walls he raised the Long Walls of Thrace to screen the approaches to the capital. The city he bequeathed was prosperous, populous — perhaps approaching half a million souls, fed by the grain fleets of Egypt — and politically combustible, its life increasingly organised around the Hippodrome and the rival circus factions, the Blues and the Greens, whose rivalries spilled regularly into bloodshed in the streets.
It was from that volatility that the defining catastrophe of Justinian’s early reign erupted. In January 532, resentment at heavy taxation — embodied in the emperor’s praetorian prefect, John the Cappadocian — and anger over the botched execution of faction members fused the normally hostile Blues and Greens into a single mob. In the Hippodrome the racing crowd turned on the emperor, and the partisan cheers gave way to a shared cry that named the revolt: Nika! — “Conquer!” For nearly a week the rioters held the streets, burned what they could reach, and proclaimed a rival emperor, Hypatius, a nephew of the late Anastasius. Justinian, besieged in the Great Palace, was on the point of flight when, according to Procopius, the empress Theodora stiffened his resolve with the declaration that the imperial purple made a fine burial shroud. The revolt ended not in negotiation but in massacre: the generals Belisarius and Mundus led their troops into the packed Hippodrome and cut down the crowd, leaving — by the chroniclers’ figures — some thirty thousand dead. Justinian kept his throne, but the heart of his capital lay in ashes.
The destruction was concentrated precisely where the city’s monumental dignity resided. The fires of the Nika revolt consumed the ceremonial core around the Augustaion: the Senate house, the Baths of Zeuxippus with their celebrated collection of antique statuary, the great bronze Chalke gate of the palace, and — most grievously — the second Hagia Sophia, the Theodosian cathedral, which burned to its foundations along with the nearby church of Hagia Eirene. In a single week the religious and civic showpieces accumulated over two centuries had been gutted. For most rulers this would have been a disaster to be patched over. Justinian treated it as an opportunity.
What followed was the most ambitious building campaign the city had ever seen, and the one that gave Constantinople the skyline it would keep for the rest of its existence. At its centre stood the new Hagia Sophia, begun within weeks of the fire and completed in less than six years. Justinian entrusted it not to builders but to two theoreticians, Anthemius of Tralles and Isidore of Miletus, who crowned a vast rectangular nave with a dome of unprecedented span, pierced at its base by a ring of windows so that the gold-lined interior seemed, to contemporaries, to be roofed in floating light. Dedicated in 537 — the emperor, tradition holds, exclaiming that he had outdone Solomon — it was the largest enclosed space in the world and an architectural gamble that nearly failed: the first dome, weakened by earthquakes, collapsed in 558 and had to be rebuilt, taller and steeper, by 562. Around this masterpiece Justinian rebuilt and multiplied. He restored Hagia Eirene; raised the elegant domed church of Saints Sergius and Bacchus, the so-called Little Hagia Sophia; and entirely reconstructed the Church of the Holy Apostles on a cruciform, five-domed plan that would become the model for sacred architecture across the Orthodox world, from Ephesus to Venice. The ruined civic centre was remade as well — a new Senate, rebuilt baths, a restored Chalke gate sheathed in mosaics of the emperor’s victories, and, rising over the Augustaion, a towering column bearing a bronze equestrian statue of Justinian himself, facing east toward Persia. Beneath the city he secured its lifeblood, enlarging the great covered reservoir now known as the Basilica Cistern, its forest of columns holding water against siege and drought.
Yet the city that Justinian left at his death in 565 was not simply the triumphant capital these monuments imply, and the contrast is the truest measure of his reign. The buildings stood at their most magnificent: Hagia Sophia’s rebuilt dome dominated a skyline studded with new churches, the harbours and cisterns had been renewed, and Constantinople had reasserted itself without rival as the greatest city of the Christian world and the showcase of a restored Roman empire that once more ruled Africa, Italy, and southern Spain. But the human city behind that façade had been gravely wounded. In 541–542 the plague that bears Justinian’s name swept through the capital, killing, by the appalled testimony of eyewitnesses, a vast share of its inhabitants — perhaps a third or more — and it returned in waves thereafter. The population that had pressed half a million strong into the Theodosian walls at his accession was sharply diminished, the treasury Anastasius had filled was drained by endless war and building, and the overextended empire was already straining at its recovered frontiers. Justinian thus bequeathed a paradox that would define Constantinople for generations: a city more splendid in stone than it had ever been, crowned by the dome that remains his monument fifteen centuries later, yet thinner in people and poorer in reserves than the one he had received — magnificent, and quietly exhausted.
The Komnenian City: The medieval apogee (1081–1180)
The Constantinople that Alexios I Komnenos seized in 1081 was a capital whose splendour had outlasted the empire’s strength. The intervening five centuries had not altered the Justinianic skeleton — Hagia Sophia still crowned the skyline, the Theodosian walls still held the line, the cisterns and harbours still functioned — but the state behind that grandeur had been shaken to its foundations. The catastrophe at Manzikert in 1071 had thrown open Anatolia, the city’s recruiting ground and breadbasket, to the Seljuk Turks; a generation of palace coups had debased the coinage and emptied the treasury; and as Alexios took the throne the Normans of Robert Guiscard were crossing the Adriatic while the Pechenegs pressed the Thracian frontier. The city itself was intact and immense, but it presided over an empire that many in the West had begun to write off. The achievement of the Komnenian century was to make Constantinople once again the unrivalled showcase of a recovering power — and, in the process, to reshape where and how the city lived.
The most visible change was a shift in the capital’s centre of gravity. The Great Palace beside the Hippodrome, the integrated precinct of power that had anchored the city since Constantine, was by now an ageing warren, and the Komnenoi increasingly abandoned it. Alexios moved the imperial residence to the Palace of Blachernae, tucked into the northwestern corner of the city against the land walls, and his grandson Manuel rebuilt it on a lavish scale, its halls glittering with gold and mosaic and gemwork that left foreign visitors groping for comparisons. The old ceremonial heart by the Augustaion did not vanish, but the living court now sat at the opposite end of the city, and the urban fabric reoriented itself accordingly — a quiet but decisive break with the topography Justinian had bequeathed.
A second transformation ran along the shore of the Golden Horn. In 1082, desperate for naval help against the Normans, Alexios granted the Venetians a sweeping charter: freedom from customs and a quarter of their own in the heart of the commercial district. It was the first of a series of concessions that would draw the Pisans and the Genoese after them, until the waterfront below the city had become a chain of Italian colonies — wharves, warehouses, churches, and tightly knit communities of Latin merchants who handled an ever-growing share of the capital’s trade. Constantinople became, in the twelfth century, the great emporium of the Mediterranean world; the Jewish traveller Benjamin of Tudela, passing through around 1160, marvelled that tribute flowed in daily to fill towers with silk and purple and gold, and judged that outside Baghdad no city on earth could match it for wealth. But the same charters that fed the city’s prosperity lodged a foreign, privileged, and increasingly resented population in its commercial core — a tension that grew sharper with every decade.
Within the walls the dynasty stamped the city with a distinctive religious architecture. The supreme monument was the monastery of Christ Pantokrator, founded by John II Komnenos and his Hungarian-born empress Eirene and completed in the 1130s: three linked churches under a cluster of domes, attached to a hospital of some fifty beds, an old-age home, and a leprosarium, and intended as the dynastic mausoleum — today it survives as the Zeyrek Mosque, the second-largest Byzantine religious structure still standing in Istanbul. Eirene also endowed the convent of Kecharitomene; the influential Komnenian relatives rebuilt the monastery of the Chora out near the Blachernae quarter. The new churches favoured by the age were smaller and more vertical than Justinian’s vast halls, their exteriors patterned in recessed brick and their interiors densely worked in marble and mosaic — an intimate, jewel-like aesthetic suited to aristocratic and monastic patrons rather than to imperial spectacle. Manuel meanwhile turned to the defences, repairing the sea walls and throwing out a new stretch of land wall — the Wall of Manuel Komnenos — to enclose and protect the exposed Blachernae district where his court now lived.
By the height of Manuel’s reign the city had become the wonder of a Western world that had begun to pour through it. The armies of the First Crusade had camped beneath its walls in 1096, and Fulcher of Chartres confessed that no one could count its riches; the Second Crusade brought through, in 1147, the French king Louis VII and his chaplain Odo of Deuil, who described a city surpassing every other in wealth even as he bristled at its pride. Pilgrims came for its incomparable hoard of relics, diplomats for its ceremony, merchants for its markets. With a population that very likely approached the half-million it had carried under Justinian, Constantinople in these years was once more, beyond dispute, the greatest Christian city on earth and the brilliant capital of an empire that under Manuel reached into Italy, Hungary, the Crusader states, and the Anatolian interior.
Yet the city Manuel left at his death in 1180 carried the same paradox that had shadowed it under Justinian, in a new and more dangerous form. It had never looked more magnificent — the gilded halls of Blachernae, the domes of the Pantokrator, the crowded wharves of the Golden Horn all testified to a century of recovery. But its prosperity now rested in the hands of foreign communes that the ordinary population had come to hate, and its stability depended on a single strong emperor at a moment when the dynasty was about to dissolve into a child’s regency and a usurper’s coup. Within two years the resentment would detonate: in 1182 the mob fell upon the Latin quarters, slaughtering the Italian inhabitants and burning their districts along the Horn. That fire was the first of the conflagrations that would consume the Komnenian city — a prelude to the far greater catastrophe of 1203–1204, when the diverted Fourth Crusade would do to Constantinople what no enemy had managed in nearly nine centuries. At Manuel’s death the apogee was real, and so, just out of sight, was the precipice.
The Palaiologan City: A golden twilight (1261–c. 1321)
When Michael VIII Palaiologos rode into Constantinople in August 1261, he entered a city that had been dying for half a century. The Fourth Crusade had stormed and sacked it in 1204, and the fifty-seven years of Latin rule that followed had been an age of slow ruin: the relics carried off to the West, the bronze horses of the Hippodrome shipped to Venice, the churches stripped of their fittings, and — most tellingly — the buildings themselves cannibalised, their lead roofs and timbers sold or burned for fuel by a Latin court too poor to maintain what it had seized. The Great Palace had decayed beyond saving; whole districts stood abandoned. The Constantinople recovered for the Byzantines almost by accident — taken by a small advance force while the Venetian fleet was away — was a shrunken, impoverished, half-empty shell of the city the Komnenoi had ruled. For the first time in the series, the dynasty that “found” the capital found not a fixed inheritance to build upon, but a wreck to be salvaged.
Michael VIII set about the salvage with the energy of a man who knew his restoration of the empire would be judged by the state of its capital. He repaired the land walls and heightened the sea defences against the Latin reconquest he feared; he repopulated emptied quarters with settlers; he restored Hagia Sophia to Orthodox worship and rebuilt churches and monasteries across the city; and he raised in front of the Church of the Holy Apostles a tall column bearing a bronze figure of the Archangel Michael, with the city held in his own kneeling hands — a monument of restoration to set against the column of Justinian. But one Justinianic and Komnenian certainty he could not revive. The old Great Palace by the Hippodrome was left to its ruin for good, and the imperial residence remained at Blachernae in the northwestern corner, where the Palaiologoi would hold their diminished court until the end.
Beneath the restoration, the deeper truth was that the city would never fill again. Behind the vast Theodosian walls, built nine centuries earlier for half a million people, much of the enclosed space reverted to fields, vineyards, orchards, and rubble; travellers came to describe Constantinople not as a single great city but as a scattering of inhabited villages strung among ruins and gardens. Its commerce, too, had slipped from Byzantine hands. By the Treaty of Nymphaeum that had bought Genoese support in 1261, Michael granted the Genoese their own town at Galata across the Golden Horn, and that fortified colony swelled into a prosperous rival that engrossed the maritime trade and the customs revenue the imperial treasury desperately needed. The capital of the restored empire was a poor city, ringed by walls it could barely garrison and overlooked by a foreign suburb richer than itself.
And yet — this is the paradox of the Palaiologan city in its sharpest form — these same straitened decades produced one of the most brilliant cultural flowerings in the whole history of Byzantium. Under Michael’s son Andronikos II (1282–1328), as the army shrank, the navy was disbanded, and the Anatolian heartland slipped away to the Turks, Constantinople became the stage for what later scholars would call the Palaiologan Renaissance. Men like Maximos Planoudes, Nikephoros Choumnos, Nikephoros Gregoras, and above all the polymath statesman Theodore Metochites revived the close study of the ancient Greek authors, of mathematics and astronomy and rhetoric, and poured their learning and their fortunes into the arts. The painting and mosaic of the age abandoned the hieratic stiffness of earlier centuries for a new grace and movement — slender figures, deep architectural backgrounds, faces of real tenderness and grief — set inside the small, elegant, intricately patterned churches that the period favoured.
The supreme emblem of this golden twilight is the monastery of the Holy Saviour in Chora, out near the land walls — today the Kariye, one of the most precious survivals of the Byzantine world. Between roughly 1316 and 1321, Theodore Metochites, grand logothete and effectively first minister of Andronikos II, rebuilt and adorned it at his own enormous expense, sheathing its narthexes and side chapel in mosaic and fresco cycles of the life of the Virgin and of Christ, a luminous Deesis, and, in the funerary chapel, an Anastasis of the Resurrection — Christ hauling Adam and Eve bodily from their tombs — that is among the masterpieces of medieval art. Over the door into the nave, Metochites had himself portrayed in his great striped turban, kneeling to offer the model of the church to an enthroned Christ. The image is the perfect distillation of the moment: a fabulously cultivated minister of a near-bankrupt empire, lavishing the resources of a lifetime on beauty rather than on armies. When civil war toppled Andronikos II in 1328, Metochites fell with him, was stripped of his wealth and exiled, and returned at the last to die as a humble monk in the very church he had made glorious.
That fall was a warning of what lay ahead. The Constantinople of about 1320 was a city more beautiful in its art than at almost any time in its past and weaker in its body than at any time since Justinian — radiant churches and learned academies set amid fields and ruins, a court of dazzling refinement presiding over a vanishing empire. The fragile balance did not hold. Within a few years the dynastic quarrel between Andronikos II and his grandson opened the first of the Palaiologan civil wars; a second and far more ruinous one tore the state apart between 1341 and 1347; and in 1347 the Black Death reached the city and carried off a great share of those who remained. From the apogee of Metochites’ Chora the road ran steadily downward — through ever-shrinking territory, deepening poverty, and growing dependence on Italian fleets and Turkish goodwill — until the morning in May 1453 when Mehmed II’s guns brought the Theodosian walls down at last, and the eleven-century history of the imperial city closed.
Remaining Byzantine monuments in modern Istanbul.
Today, while Istanbul still retains iconic monuments from its past, much of its architecture, even the most prestigious that adorned it during antiquity and the Middle Ages, has disappeared over the centuries. Today, the challenge is immense to preserve the remaining heritage, confronted with multiple risks: the conversion of Hagia Sophia and the former Church of the Pammakaristos into mosques, mass tourism, pollution, rampant urbanization, and moreover, the risk of a major earthquake, very high in Istanbul at present.
Discover our guide to the Byzantine monuments of Istanbul.
Sources and further readings.
Janin, Constantinople byzantine: développement urbain et répertoire topographique, 2nd ed. (Paris, 1964)
Runciman, The Fall of Constantinople 1453 (Cambridge, 1965)
Dagron, Naissance d’une capitale (1974)
Müller-Wiener, Bildlexikon zur Topographie Istanbuls (Tübingen, 1977)
Mango, Byzantium: The Empire of New Rome (1980)
Kazhdan (ed.), The Oxford Dictionary of Byzantium (1991)
Magdalino, The Empire of Manuel I Komnenos, 1143–1180 (Cambridge, 1993)
Donald M. Nicol, The Last Centuries of Byzantium, 1261–1453, 2nd ed. (Cambridge, 1993)
Sarah Bassett, The Urban Image of Late Antique Constantinople (Cambridge, 2004)
Harris, Constantinople: Capital of Byzantium (2017)