As is well known, the Ottoman Empire, which ruled on three continents during its history, lost the First World War along with Germany. Although the war ended in 1918, the war of Greek liberation from the Turks, ordered by Mustafa Kemal and the resistant forces in 1919, continued until 1922. When the Greek adventure failed on Turkish territory, Venizelos united all Greeks, and several Greeks from Anatolia, after their army had fled to Greece. Mustafa Kemal, in turn, wanted to draw in contemporary Turks living outside national boundaries to populate his country. Thanks to the treaty agreed on 30 January 1923 between Ataturk and Venizelos in Lausanne, the Greeks of Anatolia, of Turkish nationality but looking to the Orthodox Church, were exchanged for Muslim Turks of Greek nationality and so minorities living in both countries became refugees. This forced migration dating from 1923, called the "Great Exchange", required a census of the population: it found that more than a million people were homeless. This period, which imposed a "national reconstruction" in the history of the two countries, is remembered as a complex and multidimensional historical process. The pain and disorder that affected hundreds of thousands of people of both nationalities caused by this exchange persisted for many years. Turkey, as one of the countries that underwent a population exchange with Greece, serves as an example to the world. That's why this subject remains relevant for agendas of today.