Constantine I (Greek: Κωνσταντίνος Αʹ, Konstantínos I; 2 August [O.S. 21 July] 1868 – 11 January 1923) was King of Greece from 18 March 1913 to 11 June 1917 and from 19 December 1920 to 27 September 1922. He was commander-in-chief of the Hellenic Army during the unsuccessful Greco-Turkish War of 1897 and led the Greek forces during the successful Balkan Wars of 1912–1913, in which Greece expanded to include Thessaloniki, doubling in area and population. He succeeded to the throne of Greece on 18 March 1913, following his father's assassination.