King Constantine I was the King of Greece from 1913 to 1917 and again from 1920 to 1922. He was born on August 2, 1868, and was a member of the House of Glücksburg. His reign was marked by political turmoil and military challenges, particularly during World War I, when he faced pressure from both the Allies and the Central Powers. Constantine's decision to remain neutral during the war led to conflicts with the Greek government and ultimately resulted in his abdication in 1917. He returned to the throne in 1920 but was forced to flee again after Greece's defeat in the Greco-Turkish War in 1922. He died in exile on January 11, 1923.