Constantinople to Istanbul

Byzantium and New Rome

Legend says the Greek city of Byzantium was founded about 657 BCE by Byzas, leader of settlers from Megara. When Constantine the Great dedicated it as his capital in 330 CE he called it New Rome, but its coins went on reading Byzantium until he ordered them changed to Constantinopolis, the city of Constantine.^[1]

Greek speakers often called it simply “the City”. By the end of the first millennium they spoke of going eis tēn polin, “into the City”, rather than “to Constantinople”, and by the 13th century the phrase had become a name for the place, Istinpolin, which over the centuries turned into Istanbul.^[1] The Turkish historian Ekrem Buğra Ekinci thinks it more likely a worn-down form of Constantinopolis.^[4]

1453: a new ruler, not a new name

Mehmed II’s cannon breached the land walls in 1453, and the Ottomans moved their capital there from Edirne in 1457.^[1] They did not formally rename it. “It’s a fact that the Ottomans called Istanbul ‘Kostantiniyye,’ among other names, in thousands of their official documents,” says Christoph Herzog of the University of Bamberg.^[3]

Ottoman coins were generally struck “in Qustuntunia”, and decrees were dated from there, while in everyday speech people said Istanbul. At times sultans preferred other names: an order of 1774 asked for Islambol, “abundance of Islam”, and in 1915 the Young Turks ordered the use of Dar al-Khilafa al-Aliyyah, “the High Abode of the Caliphate”; neither lasted.^[4]

Made official by the post office

The Ottoman sultanate was abolished in 1922 and the Republic of Turkey founded in 1923.^[3] On 3 January 1929 Turkey’s post office wrote to the Universal Postal Union asking that Istanbul be used instead of Constantinople or Stamboul, and under the Postal Service Law of 28 March 1930 letters from abroad addressed to Constantinople were to be sent back.^[4] Until then, Britannica notes, the city had still officially borne the name Constantinople.^[1]

The US State Department and other governments switched to Istanbul that same year.^[3] Greeks never took to the name Istanbul, and have long called the city simply the Polis.^[2]

“It’s a fact that the Ottomans called Istanbul ‘Kostantiniyye,’ among other names, in thousands of their official documents.”^[3]