Greco-Turkish Population Exchange

The 1923 population exchange between Greece and Turkey (Greek: Ἡ Ἀνταλλαγή, Turkish: Mübâdele) stemmed from the "Convention Concerning the Exchange of Greek and Turkish Populations" signed at Lausanne, Switzerland, on 30 January 1923, by the governments of Greece and Turkey. It involved approximately 2 million people (around 1.2 million Greeks from Asia Minor, Eastern Thrace, Trabzon, the Pontic Alps and the Caucasus, and 400,000 Muslims in Greece), most of whom were forcibly made refugees and de jure denaturalized from their homelands.

By the end of 1922, the vast majority of native Asia Minor Greeks had fled the recent Greek genocide (1914–1922) and Greece's later defeat in the Greco-Turkish War (1919–1922). According to some calculations, during the autumn of 1922, around 900,000 Greeks had arrived in Greece. According to Fridtjof Nansen, before the final stage, in 1922, of the 900,000 Greek refugees a third were from Eastern Thrace, with the other two thirds being from Asia Minor.

The population exchange was envisioned by Turkey as a way to formalize, and make permanent, the exodus of Greeks from Turkey, while initiating a new exodus of a smaller number of Muslims from Greece to supply settlers for occupying the newly depopulated regions of Turkey, while Greece saw it as a way to supply its masses of new propertyless Greek refugees from Turkey with lands to settle from the exchanged Muslims of Greece.

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Wikipedia