not included administratively. This definition excludes Sverdlovsk Oblast and Chelyabinsk Oblast, both of which are included in some wider definitions of Siberia. Other sources may use either a somewhat wider definition that states the Pacific coast, not the watershed, is the eastern boundary (thus including the whole Russian Far East), as well as all Northern Kazakhstan is its subregion in the south-west or a somewhat narrower one that limits Siberia to the Siberian Federal District (thus excluding all subjects of other districts). In Russian, 'Siberia' is commonly used as a substitute for the name of the federal district by those who live in the district itself, but less commonly used to denote the federal district by people residing outside of it. Due to the different interpretations of Siberia, starting from Tyumen, to Chita, the territory generally defined as 'Siberia', some people will define themselves as 'Siberian', while others not. A number of factors in recent years, including the fomenting of 'Siberian separatism' have made the definition of the territory of Siberia a potentially controversial subject. In the eastern extent of Siberia there are territories which are not clearly defined as either Siberia or the Far East, making the question of 'what is Siberia?' one with no clear answer, and what is a 'Siberian', one of self-identification. Major cities The most populous city of Siberia, as well as the third most populous city of Russia, is the city of Novosibirsk. Present-day Novosibirsk is an important business, science, manufacturing and cultural center of the Asian part of Russia. Omsk played an important role in the Russian Civil War serving as a provisional Russian capital, as well in the expansion into and governing of Central Asia. In addition to its cultural status, it has become a major oil-refining, education, transport and agriculture hub. Other historic cities of Siberia include Tobolsk (the first capital and the only kremlin in Siberia), Tomsk (formerly a wealthy merchant's town) and Irkutsk (former seat of Eastern Siberia's governor general, near lake Baikal). Other major cities include: Barnaul, Kemerovo, Krasnoyarsk, Novokuznetsk, Tyumen. Wider definitions of geographic Siberia also include the cities of: Chelyabinsk and Yekaterinburg in the Urals, Khabarovsk and Vladivostok in the Russian Far East, and even Petropavlovsk in Kazakhstan and Harbin in China. Economy Novosibirsk is the largest by population and the most important city for the Siberian economy; with an extra boost since 2000 when it