Alexander Vasilyevich Kolchak (November 4, 1874, Saint Petersburg, February 7, 1920, Irkutsk) was a Russian military and political figure, as well as an oceanographer and polar explorer, participating in expeditions in 1900 and 1903. He became famous as a naval commander in 1915 and 1917 and is remembered as a leader of the White movement during the Russian Civil War. From November 1918 to January 1920, Kolchak served as the Supreme Ruler of Russia and the Supreme Commander of the Russian Army.