Omsk is the administrative center and largest city of Omsk Oblast, Russia. It is situated in southwestern Siberia, and has a population of over 1 million. Omsk is the second-largest city in Siberia after Novosibirsk, and is ninth-largest city in Russia. It is an essential transport node, serving as a train station for the Trans-Siberian Railway and as a staging post for the Irtysh River.
During the Imperial era, Omsk was the seat of the Governor General of Western Siberia and, later, of the Governor General of the Steppes. For a brief period during the Russian Civil War in 1918–1920, it served as the capital of the anti-Bolshevik Russian State and held the imperial gold reserves.
Omsk serves as the episcopal see of the bishop of Omsk and Tara, as well as the administrative seat of the Imam of Siberia. The mayor is
Oksana Fadina.