Tatarstan (tătˌərstănˈ, –stänˈ) [key], Tatar Republic täˈtər, tətärˈ, or Tataria tətärˈēə, republic (1990 est. pop. 3,660,000), 26,255 sq mi (68,000 sq km), E European Russia, in the middle Volga and lower Kama river valleys. Kazan is the capital; other important cities are Almetevsk, Leninogorsk, and Bugulma. The low, rolling plain that makes up most of the republic's territory yields fodder crops, wheat and other cereals, sugar beets, sunflowers, and flax. The republic is a leading Russian oil and natural-gas producer and the starting point for a pipeline to Eastern Europe. There are also important deposits of brown coal, limestone, gypsum, dolomite, and marl. Lumbering and food, leather, oil refining, and fur processing are major Tatar industries. Manufactures include machinery, chemicals, and pharmaceuticals. The Volga, Kama, Belaya, and Vyatka rivers are important for both transportation and irrigation. There are several hydroelectric stations.
Turko-Tatars make up around 50% of the population, and most live in rural areas. Russians, generally urban, constitute some 40%, and there are Chuvash, Udmurt, Mari, and Mordovian minorities. Sunni Islam is the chief religion.
Bulgars dominated the region from the 8th to 13th cent., when it was conquered by the Mongols of the Golden Horde; their Tatar descendants, in turn, gradually replaced or absorbed the Bulgar population. Russian colonization followed the capture (1552) by Czar Ivan IV of the khanate of Kazan, the most powerful of the Tatar states emerging from the empire of the Golden Horde. The Tatar ASSR was organized in 1920 as one of the first autonomous areas established by the Soviet government. In 1990 a declaration of sovereignty was adopted, and in 1991 the republic declared itself independent. This declaration was recognized by no other state. The republic was not a signatory to the Mar. 31, 1992, treaty that established the Russian Federation (see Russia), but it signed a power-sharing treaty with Russian government in 1994. Russian legislation (2003) forced a renegotiation of the treaty; a new treaty was finally ratified in 2007.