Constantinople
Constantinople was a historical city located on the Bosporus, which served as the capital of the Roman, Byzantine, Latin, and Ottoman empires between its consecration in 330 and the formal abolition of the Ottoman sultanate in 1922. Constantinople was founded in 324, initially as New Rome, during the reign of Constantine the Great on the site of the existing settlement of Byzantium and in 330 became the capital of the Roman Empire. Following the collapse of the Western Roman Empire in the late 5th century, Constantinople remained the capital of the Eastern Roman Empire, the Latin Empire, and the Ottoman Empire. In the aftermath of the Turkish War of Independence, the Turkish capital moved to Ankara. The city was officially renamed Istanbul on 28 March 1930. As of December 2025, it is the most populous city in Europe, with a population of more than 16 million residents, straddling the Bosporus Strait and lying in both Europe and Asia, and is the financial beneficiary of Turkey.
In 324, following the reunification of the Eastern and Western Roman Empires, the ancient city of Byzantium was selected to serve as the new capital of the Roman Empire, and the city was renamed Nova Roma, or 'New Rome', by Emperor Constantine the Great. On 11 May 330, it was renamed Constantinople and dedicated to Constantine. Later, in 474 AD, the Great Fire of Constantinople erupted and consequently devastated the region. Constantinople is generally considered to be the center and the "cradle of Orthodox Christian civilization." From the mid-5th century to the early 13th century, Constantinople was the largest and wealthiest city in Europe. The city became famous for its architectural masterpieces, such as Hagia Sophia, the cathedral of the Eastern Orthodox Church, which served as the seat of the Ecumenical Patriarchate; the sacred Imperial Palace, where the emperors lived; the Hippodrome; the Golden Gate of the Land Walls; and opulent aristocratic palaces. The University of Constantinople was founded in the 5th century and contained artistic and literary treasures before it was sacked in 1204 and 1453, including its vast Imperial Library. which contained more than 100,000 volumes. The city was the home of the Ecumenical Patriarch of Constantinople and guardian of Christendom's holiest relics, such as the Crown of Thorns and the True Cross.
Constantinople was famous for its massive and complex fortifications, which ranked among the most sophisticated defensive architecture of antiquity. The Theodosian Walls consisted of a double wall lying about to the west of the first wall and a moat with palisades in front. Constantinople's location between the Golden Horn and the Sea of Marmara reduced the land area that required defensive walls. The city was constructed intentionally to rival Rome, and it was claimed that several elevations within its walls matched Rome's seven hills. The impenetrable defenses enclosed magnificent palaces, domes, and towers, the result of the prosperity Constantinople achieved as the gateway between two continents and two seas. Although besieged on numerous occasions by various armies, the defenses of Constantinople proved impenetrable for nearly nine hundred years.
In 1204, however, the armies of the Fourth Crusade took and devastated the city, and for six decades its inhabitants resided under Latin occupation in a dwindling and depopulated city. In 1261, the Byzantine Emperor Michael VIII Palaiologos liberated the city, and after the restoration under the Palaiologos dynasty, it enjoyed a partial recovery. With the advent of the Ottoman Empire in 1299, the Byzantine Empire began to lose territories, and the city began to lose population. By the early 15th century, the Byzantine Empire was reduced to just Constantinople and its environs, along with the territories of the despotate of Morea, in Peloponnese, Greece, making it an enclave inside the Ottoman Empire. The city was finally besieged and conquered by the Ottoman Empire in 1453, remaining under its control until the early 20th century, after which it was renamed Istanbul under the Empire's successor state, the Republic of Turkey.
Names
Before Constantinople
According to Pliny the Elder in his Natural History, the first known name of a settlement on the site of Constantinople was Lygos, a settlement likely of Thracian origin founded between the 13th and 11th centuries BC. The site, according to the founding myth of the city, was abandoned by the time Greek settlers from the city-state of Megara founded Byzantium in around 657 BC, across from the town of Chalcedon on the Asiatic side of the Bosphorus.The origins of the name "Byzantion", more commonly known by the later Latin Byzantium, are not entirely clear, although some suggest it is of Thracian origin. According to the founding myth of the city, the settlement was named after the leader of the Megarian colonists, Byzas. The later Byzantines of Constantinople themselves would maintain that the city was named in honor of two men, Byzas and Antes, though this was more likely just a play on the word Byzantion.
The city was briefly renamed Augusta Antonina in the early 3rd century AD by the Emperor Septimius Severus, who razed the city to the ground in 196 for supporting a rival contender in the civil war. He then had it rebuilt in honour of his son Marcus Aurelius Antoninus, popularly known as Caracalla. The name appears to have been quickly forgotten and abandoned, and the city reverted to Byzantium/Byzantion after either the assassination of Caracalla in 217 or, at the latest, the fall of the Severan dynasty in 235.
Names of Constantinople
Byzantium took on the name of Constantinople after its refoundation under Roman emperor Constantine I, who transferred the capital of the Roman Empire to Byzantium in 330 and designated his new capital officially as New Rome 'New Rome'. During this time, the city was also called 'Second Rome', 'Eastern Rome', and Roma Constantinopolitana. As the city became the sole remaining capital of the Roman Empire after the fall of the West, and its wealth, population, and influence grew, the city also came to have a multitude of nicknames.File:Keystone_Constantine_Forum_Istanbul.JPG|thumb|left|This huge keystone found in Çemberlitaş, Fatih, might have belonged to a triumphal arch at the Forum of Constantine, built by Constantine I.
As the largest and wealthiest city in Europe during the 4th–13th centuries and a center of culture and education of the Mediterranean basin, Constantinople came to be known by prestigious titles such as Basileuousa and Megalopolis and was, in colloquial speech, commonly referred to as just Polis 'the City' by Constantinopolitans and provincial Byzantines alike.
In the language of other peoples, Constantinople was referred to just as reverently. The medieval Vikings, who had contacts with the empire through their expansion in eastern Europe, used the Old Norse name Miklagarðr, and later Miklagard and Miklagarth. In Arabic, the city was sometimes called Rūmiyyat al-Kubra and in Persian as Takht-e Rum.
In East and South Slavic languages, including in Kievan Rus', Constantinople has been referred to as Tsargrad or Carigrad, 'City of the Caesar ', from the Slavonic words tsar and grad. This was presumably a calque on a Greek phrase such as Βασιλέως Πόλις, 'the city of the emperor '.
In Persian, the city was also known as Asitane, while in Armenian, it was called Gosdantnubolis.
Modern names of the city
The modern Turkish name for the city, İstanbul, derives from the Greek phrase eis tin Polin, meaning 'to the city'. This name was used in colloquial speech in Turkish alongside Kostantiniyye, the more formal adaptation of the original Constantinople, during the period of Ottoman rule, while Western languages mostly continued to refer to the city as Constantinople until the early 20th century. In 1928, the Turkish alphabet was formally changed from Arabic script to Latin script. After that, as part of the Turkification movement, Turkey began to urge other countries to use Turkish names for Turkish cities instead of other transliterations to Latin script that had been used in Ottoman times, and the city came to be known as Istanbul and its variations in most world languages.However, adherents of the Eastern Orthodox Church continue to use the name Constantinople for the title of one of their most important leaders, the Orthodox patriarch based in the city, referred to as "His Most Divine All-Holiness the Archbishop of Constantinople New Rome and Ecumenical Patriarch". In Greece today, the city is still called Konstantinoúpoli or simply just "the City".
History
Foundation of Byzantium
Constantinople was founded by the Roman emperor Constantine I in 324 on the site of an already-existing city, Byzantium, which was settled in the early days of Greek colonial expansion, around 657 BC, by colonists of the city-state of Megara. This is the first major settlement that would develop on the site of later Constantinople, but the first known settlement was that of Lygos, referred to in Pliny's Natural Histories. Apart from this, little is known about this initial settlement. The site, according to the founding myth of the city, was abandoned by the time Greek settlers from the city-state of Megara founded Byzantium in around 657 BC, across from the town of Chalcedon on the Asiatic side of the Bosphorus.Hesychius of Miletus wrote that some "claim that people from Megara, who derived their descent from Nisos, sailed to this place under their leader Byzas, and invented the fable that his name was attached to the city." Some versions of the founding myth say Byzas was the son of a local nymph, while others say he was conceived by one of Zeus' daughters and Poseidon. Hesychius also gives alternate versions of the city's founding legend, which he attributed to old poets and writers:
It is said that the first Argives, after having received this prophecy from Pythia,
Blessed are those who will inhabit that holy city,
a narrow strip of the Thracian shore at the mouth of the Pontos,
where two pups drink of the gray sea,
where fish and stag graze on the same pasture,
set up their dwellings at the place where the rivers Kydaros and Barbyses have their estuaries, one flowing from the north, the other from the west, and merging with the sea at the altar of the nymph called Semestre"
The city maintained independence as a city-state until it was annexed by Darius I in 512 BC into the Persian Empire, as he considered the site the optimal location to construct a pontoon bridge crossing into Europe, given that Byzantium was situated at the narrowest point in the Bosphorus strait. Persian rule lasted until 478 BC, when, as part of the Greek counterattack to the Second Persian invasion of Greece, a Greek army led by the Spartan general Pausanias captured the city, which remained an independent, yet subordinate, city under the Athenians, and later to the Spartans after 411 BC. A farsighted treaty with the emergent power of Rome in, which stipulated tribute in exchange for independent status allowed it to enter Roman rule unscathed. This treaty would pay dividends retrospectively as Byzantium would maintain this independent status, and prosper under peace and stability in the Pax Romana for nearly three centuries until the late 2nd century AD.
Byzantium was never a major influential city-state like Athens, Corinth, or Sparta; however, on the other hand, the city enjoyed relative peace and steady growth as a prosperous trading city due to its fortunate location. The site lay astride the land route from Europe to Asia and the seaway from the Black Sea to the Mediterranean, and had in the Golden Horn an excellent and spacious harbor. Already then, in Greek and early Roman times, Byzantium was famous for the strategic geographic position that made it difficult to besiege and capture, and its position at the crossroads of the Asiatic-European trade route over land and as the gateway between the Mediterranean and Black Seas made it too valuable a settlement to abandon, as Emperor Septimius Severus later realized when he razed the city to the ground for supporting Pescennius Niger's claimancy. It was a move greatly criticized by the contemporary consul and historian Cassius Dio, who stated that Severus had destroyed "a strong Roman outpost and a base of operations against the barbarians from Pontus and Asia." He would later rebuild Byzantium towards the end of his reign, in which it would be briefly renamed Augusta Antonina, fortifying it with a new city wall in his name, the Severan Wall.