Greco-Turkish War (1919–1922)
The Greek campaign was launched primarily because the western Allies, particularly British Prime Minister David Lloyd George, had promised Greece territorial gains at the expense of the Ottoman Empire, recently defeated in World War I. The armed conflict started when the Greek forces landed in Smyrna (now Izmir), on 15 May 1919. They advanced inland and took control of the western and northwestern part of Anatolia, including the cities of Manisa, Balıkesir, Aydın, Kütahya, Bursa and Eskişehir. Their advance was checked at the Battle of Sakarya in 1921 by forces of the Turkish national movement. The Greek front collapsed with the Turkish counter-attack in August 1922, and the war effectively ended with the recapture of Smyrna by the Turkish forces and the Great Fire of Smyrna.
Fridtjof Nansen
After the Greco-Turkish War of 1919–1922, Nansen travelled to Istanbul to negotiate the resettlement of hundreds of thousands of refugees, mainly ethnic Greeks who had fled from Turkey after the defeat of the Greek Army. The impoverished Greek state was unable to take them in, and so Nansen devised a scheme for a population exchange whereby half a million Turks in Greece were returned to Turkey, with full financial compensation, while further loans facilitated the absorption of the refugee Greeks into their homeland. Despite some controversy over the principle of a population exchange, the plan was implemented successfully over a period of several years.