Which city became Turkey's capital on October 13, 1923?

Ankara became Turkey’s capital on October 13, 1923.

Ankara replaced Constantinople, now Istanbul, as the capital of Turkey on October 13, 1923, shortly before the Republic of Turkey was formally proclaimed on October 29. The decision marked the political break between the new republic and the Ottoman imperial past.

During the Turkish War of Independence, Mustafa Kemal Atatürk and the nationalist movement established their headquarters in Ankara. The city was inland and central to the nationalist-controlled territory, while Istanbul remained under Allied occupation after the First World War. Ankara therefore became the centre of the emerging republican government.

The city was historically known in Western languages as Angora and has much older roots, including Roman and Galatian periods. After becoming the capital, it expanded rapidly with government offices, embassies and new districts such as Yenişehir. Istanbul remains Turkey’s largest and most internationally famous city, but Ankara is the constitutional and administrative capital.