Tomsk Oblast (Russian: То́мская о́бласть, Tomskaya oblast) is a federal subject of Russia (an oblast). It lies in the southeastern West Siberian Plain, in the southwest of the Siberian Federal District. Its administrative center is the city of Tomsk. Population: 1,047,394 (2010 Census).The development of the territory which now constitutes the oblast began in the early 17th century. Tomsk itself was founded in 1604.