How a Greek legend and a Roman emperor built the world's most coveted city

History · Published 3 October 2026 Swipe more like this →

In short: For over 2,500 years, Istanbul has served as a strategic bridge between Europe and Asia. Once known as Byzantium and later Constantinople, this city has survived fires, earthquakes, and sieges to remain a global crossroads. Its name evolved through centuries of linguistic shifts, finally becoming Istanbul in 1930.

The city’s origins are steeped in both archaeology and myth. Legend credits Byzas, a leader from the Greek city of Megara, with establishing Byzantium around 657 BCE after seizing the peninsula from Thracian tribes. By the 2nd century CE, the city faced destruction after opposing Roman emperor Septimius Severus in a civil war. Severus later rebuilt the settlement, briefly renaming it Augusta Antonina to honor his son.

The city’s true transformation began in 330 CE when Constantine the Great dedicated it as his new capital, calling it New Rome. Although he officially named it Constantinopolis, locals often referred to it simply as 'the City.' Over centuries of linguistic evolution, this Greek phrase morphed into the name Istanbul. It remained the capital of the Byzantine Empire until 1453, when Ottoman sultan Mehmed II breached the city's formidable land walls with heavy cannons.

Geography has always dictated the city's fate. Straddling the Bosporus, the city sits between the Black Sea and the Mediterranean, connected by the Sea of Marmara and the Golden Horn. This location made it a vital center for trade and imperial power, though it also invited constant conflict. Despite enduring numerous disasters, the city’s historic core remains a UNESCO World Heritage site, where ancient masonry and modern infrastructure coexist.

Today, the city’s landscape is defined by its seven hills and the complex currents of the Bosporus, where salty Mediterranean water flows beneath the colder Black Sea surface. While the capital of Turkey moved to Ankara in 1923, Istanbul remains the nation's largest city and a primary seaport, continuing its long history as a bridge between conflicting surges of culture and religion.

General information, not professional advice. Spotted an error? Flag the card or see corrections and complaints.

Intellect Plus is a visual educational discovery platform for exploring fascinating facts and ideas. Brain Food, Not Brain Rot. What is Intellect Plus?

Related

• Istanbul has been known by many names, but none were ever Constantinople to the Turks.
• One megacity, two continents, four imperial capitals
• Constantine’s New Rome ruled until Ottoman 1453
• This global location uniquely spans across two distinct continents, namely Asia and Europe
• The Byzantines never called their empire Byzantine; a German historian did in 1555
• From Sunda Kelapa to Batavia: The turbulent evolution of Indonesia's capital city
• Why Illinois is a tale of two states divided by geography and history
• From Redware to Independence: The complex, often brutal, history of Jamaica
• Iceland was the last major landmass on Earth to be settled by humans
• From Paleolithic hunters to a modern monarchy, Jordan’s history spans millennia of human innovation.
• How a nomadic steppe confederation transformed into a medieval European powerhouse
• Kentucky was once a contested frontier, defined by ancient mounds and bloody colonial expansion.

More in History by country, small region and city · More in History · Latest · A–Z · All topics