Mustafa İsmet İnönü was a Turkish general and statesman, who served as the second President of Turkey from 10 November 1938 to 27 May 1950, when his Republican People's Party was defeated in Turkey's second free elections. He also served as the first Chief of the General Staff from 1922 to 1924, and as the first Prime Minister after the declaration of the Republic, serving three terms: from 1923 to 1924, 1925 to 1937, and 1961 to 1965. As President, he was granted the official title of "Milli Şef".
When the 1934 Surname Law was adopted, Mustafa Kemal gave him a surname taken from İnönü, where he commanded the forces of Army of Grand National Assembly as the Minister of the Chief of the General Staff during the Greco-Turkish War of 1919–1922. Afterwards these battles became to be known as the First Battle of İnönü and Second Battle of İnönü.