Constantinople

The city historically known as Constantinople was a major urban centre on the Bosporus that served as the capital of four successive empires: the Roman, Byzantine, Latin and Ottoman empires. Founded on the site of ancient Byzantium and consecrated as Nova Roma—“New Rome”—in 330 CE, it became one of the most significant cities of the pre-modern world. Although the name Istanbul had already been used in local speech for centuries, the city was officially renamed Istanbul in 1930. It remains Turkey’s largest city and an important cultural and financial hub, uniquely spanning both Europe and Asia.

Historical Background

In 324 CE, Emperor Constantine the Great selected the ancient settlement of Byzantium as the new capital of a reunified Roman Empire. On 11 May 330 the city was formally dedicated and renamed Constantinople. After the fall of the Western Roman Empire in the late fifth century, Constantinople continued as the capital of the Eastern Roman (Byzantine) Empire until its temporary replacement under the Latin Empire (1204–1261). It was restored to Byzantine rule in 1261 and remained an imperial capital until its conquest by the Ottoman Empire in 1453. Under Ottoman rule it continued as a political and cultural centre until the abolition of the empire in 1922.
Following the Turkish War of Independence, the capital was transferred to Ankara. Although Constantinople had long been referred to as Istanbul, the name was formally adopted in 1930.

Urban Prestige and Significance

From the fifth to the thirteenth century, Constantinople was the largest and wealthiest city in Europe, renowned for its monumental architecture and cultural institutions. Its celebrated landmarks included:

• Hagia Sophia, the patriarchal cathedral of the Eastern Orthodox Church.
• The Great Palace of Constantinople, residence of Byzantine emperors.
• The Hippodrome, a social and ceremonial space.
• The Theodosian Land Walls, one of antiquity’s most formidable defensive systems.

The University of Constantinople, established in the fifth century, housed extensive artistic, literary and scholarly resources, including the Imperial Library, which preserved significant remnants of ancient Greek literature.
Strategically positioned between the Golden Horn and the Sea of Marmara, the city formed a natural defensive triangle further protected by an elaborate moat and double-wall system. Built to rival Rome, it occupied seven hills within its boundaries and served as the principal guardian of Christian relics, including the Crown of Thorns and the True Cross.
Despite repeated sieges, the city endured for centuries until the Fourth Crusade captured it in 1204. The Byzantine restoration of 1261 brought partial revival, but ongoing territorial losses to the rising Ottoman state left Constantinople isolated. The city finally fell in 1453 and continued under Ottoman rule for nearly five hundred years.

Before Constantinople: Earlier Names

The earliest known name for the settlement, according to Pliny the Elder, was Lygos, probably a Thracian foundation dating from between the thirteenth and eleventh centuries BCE. By the time Greek colonists from Megara arrived around 657 BCE, the site is believed to have been abandoned. The settlers established the city of Byzantion (Latin: Byzantium), a name of uncertain origin but often linked to the legendary founder Byzas.
In the early third century CE, Emperor Septimius Severus briefly renamed the city Augusta Antonina in honour of his son Caracalla after punishing it for supporting a rival claimant to the throne. This name soon fell out of use, and the city reverted to Byzantium until its refoundation by Constantine.

Names Adopted After the Refoundation

With Constantine’s transformation of the city into the new imperial capital in 330 CE, Byzantium became:

• Constantinople (Κωνσταντινούπολις), meaning “City of Constantine”.
• Nova Roma or New Rome, its official imperial designation.
• Second Rome or Eastern Rome, reflecting its rising prominence.

Over time, the city acquired a series of honorific titles that reflected its grandeur:

• Basileuousa – “Queen of Cities”.
• Megalopolis – “The Great City”.
• Polis – simply “The City”, used colloquially by Byzantines and echoing its unrivalled status.

Names in Other Languages and Cultures

Due to its prestige, Constantinople held evocative titles in many cultures:

• Miklagarðr / Miklagard in Old Norse, “Great City”, used by Scandinavian Varangians.
• Rūmiyyat al-Kubrā in Arabic, “Great City of the Romans”.
• Takhte-Rum in Persian, “Throne of the Romans”.
• Tsargrad / Carigrad in East and South Slavic languages, “City of the Caesar”.
• Asitane in Persian, “Threshold of the State”.
• Gosdantnubolis in Armenian, “City of Constantine”.

These names highlight Constantinople’s cross-cultural importance as the political, economic and religious centre of the eastern Mediterranean world.

Istanbul: Etymology and Modern Usage

The modern name Istanbul derives from the Medieval Greek phrase εἰς τὴν Πόλιν (eis tin Polin), meaning “into the City”, reflecting the habit of Greek speakers referring to Constantinople simply as The City. This colloquial form passed into Turkish usage alongside the formal Ottoman name Kostantiniyye, an adaptation of Constantinople.
Western languages continued to prefer “Constantinople” until the twentieth century. After the alphabet reform in Turkey in 1928 and further administrative changes, the name Istanbul was officially adopted in 1930.