The Greco-Turkish War of 1919–1922 was fought between Greece and the Turkish National Movement during the partitioning of the Ottoman Empire in the aftermath of World War I, between 15 May 1919 and 14 October 1922. This conflict was a part of the Turkish War of Independence.
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. Greek claims stemmed from the fact that Western Anatolia had been part of Ancient Greece and the Byzantine Empire before the Turks conquered the area in the 12th–15th centuries. The armed conflict started when the Greek forces landed in Smyrna (now İzmir), on 15 May 1919.