After the Greco-Turkish War of 1919–1922, Nansen travelled to Constantinople 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.