Peter the Great in his search for gold sent Cossacks up the Irtysh River, but the expedition met local nomads and had to stop. Cossacks laid a fortress in the mouth of the Om’ river, and that was how the city of Omsk was founded in 1716. The fortress allowed peasants to start farming on neighboring territories. In 1782 Omsk fortress became a town within Tobolsk region, and three years after the town acquired the coat-of–arms.

Apart military and administrative functions, Omsk was a cultural and trade centre. Since 1839 Omsk officially became administrative centre of Western Siberia. The city was a base for researchers of Siberia and Central Asia – Alexander Humboldt, Alfred Brehm, Peter Semenov-Tien-Shansky and other eminent travelers and natural scientists visited Omsk. In 1877 a branch of Royal Russian Geographic Society opened in Omsk.

History of Omsk, like many other Siberian cities, is closely linked with history of Russian political exiles. Decembrists, participants of Petrashevsky Circle, populists and members of other revolutionary movements and organization greatly affected Siberian population by their education, ideology, wide scientific interests and social demands. World famous Russian writer Fedor Dostoevsky was also among prisoners of Omsk jails. He described his life in Omsk in “The House of The Dead”. Polish riot of 1830-1831 added 2000 new citizens to Omsk population – these were Poles, exiled for their involvement in the riot. Early 1860s, notable for active revolutionary and national liberation movement, witnessed a powerful wave of new political exiles. After the riot of 1863 Western Siberia hosted nearly 11 000 Polish exiles, 2000 of which live in Omsk. Among exiles there were eminent Russian writers and researchers.

End of 19th and beginning of 20th centuries was a time of great change for Siberia. Massive migration of peasants caused an explosive development of economy, especially agriculture, and Great Siberian railroad provided connection of local merchants with other Russian and European markets. Omsk rapidly turned into a large trade, transport and industrial centre of Western Siberia with a large group of foreign businessmen. In 1911 Omsk welcomed Western Siberian Forest, Agricultural and Industrial Exhibition.

In 1918 Omsk became the center of anti-Soviet movement in Russia. On November 18, 1918 admiral Kolchak proclaimed himself a supreme governor of Russia, and Omsk hosted so-called Russian Government for one year, until the Red Army brought back Soviet regime in November 1919. During 1930s thousands of peasant families were subjected to forced collectivization and moved to swamps, where many of them died. Such cruel governmental orders caused peasant revolts, which were put down. Parts of famous GULAG archipelago were located in the Omsk region.

1920s and 1940s were the dawn of Omsk industry. During the World War II Omsk hosted about 100 industrial enterprises, evacuated from European part of the USSR. These enterprises became the base for rapid progress of local machine-building industry. After the war, Omsk became the largest Soviet centre of petroleum chemistry.