After World War I, Greece began the Occupation of Smyrna and of surrounding areas of Western Anatolia in 1919 at the invitation of the victorious Allies, particularly British Prime Minister David Lloyd George. The occupation was given official status in the 1920 Treaty of Sèvres, with Greece being awarded most of Eastern Thrace and a mandate to govern Smyrna and its hinterland.[7] Smyrna was declared a protectorate in 1922, but the attempted enosis failed since the new Turkish Republic prevailed in the resulting Greco-Turkish War of 1919–1922, when most Anatolian Christians who had not already fled during the war were forced to relocate to Greece in the 1923 population exchange between Greece and Turkey.