The monograph considers a wide range of issues of the early history of the Cossacks Berezov and Surgut - the first Russian cities of the Northern Ob region. The author determines the origin, composition, number, sources of formation of the main category of the military-service population of the Ugra land in the late XVI - early XVII centuries.; the role of local Cossacks in the colonization of the "Siberian country" in the first decades after the "Ermakov capture" of this vast region is being clarified; the specifics of the Cossack villages are revealed - and formed at the foundation of Berezov and Surgut, and existed until the 1620s. inclusive, along with the units of "Lithuania," Cherkasy, newly baptized, as well as boyar children.