Convention Concerning the Exchange of Greek and Turkish Populations

The Convention Concerning the Exchange of Greek and Turkish Populations, also known as the Lausanne Convention, was an agreement between the Greek and Turkish governments signed by their representatives in Lausanne on 30 January 1923, in the aftermath of the Greco-Turkish War of 1919–1922. The agreement provided for the simultaneous expulsion of Orthodox Christians from Turkey to Greece and of Muslims from Greece (particularly from the north of the country) to Turkey. The population transfers involved approximately two million people, around 1.5 million Anatolian Greeks and 500,000 Muslims in Greece.

With respect to the Muslims of Greece the treaty reflected Ottoman conceptions of 'nationality' in that their actual ethnic origins was superseded by religious affiliation. That meant that many Greek Muslims from Greek Macedonia and Epirus were classified as Turks and so were forced to leave their homes, despite the fact that many spoke little or no Turkish and actually descended from Ottoman-era Greek converts to Islam. Similarly, many Turkish Christians from north-eastern Anatolia and Cappadoccia were also classified as Greeks and were deported to Greece although they spoke little or no Greek. Such groups include Karamanlides, who spoke Karamanli Turkish. Because the Convention classified Greeks and Turks according to religious affiliation, they were also expelled to Greece alongside Greek-speaking Anatolian Christians.

For the same reason, many historic cases of Pontic Greeks from northeastern Anatolia and the Trans-Caucasus region who had converted to Islam and adopted the Turkish-language and national identity were simply classified for the purposes of the Convention as 'Turks'. However, large numbers from that Pontic Greek community had remained Crypto-Christians into the late Ottoman period, before reverting to their ancestral Christian Orthodox faith following the 1828 Russian occupation of Erzurum and Gumushane, when they joined the invading forces and then followed the Russian Imperial Army back into Georgia and southern Russia upon its withdrawal.

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