The Russian ethnos was consolidated during the course of the first millennium C.E. from a large number of small tribes living in the northern part of present-day Russian territory. Beginning in the fourteenth and fifteenth centuries, they spread out to the south and east, occupying the Don region, the northern Black Sea coast, the valley of the Terek River, and parts of the Transcaucasus and Siberia. In the process, the Russians absorbed many small originally Finnic-speaking and Turkic-speaking ethnic groups, which are now indistinguishable from them in language and culture. (Other groups remain encapsulated within Russian territory; some of them had autonomous status under the Soviet government.) During the southward migration, the Russian ethnos also absorbed large numbers of people who were originally Ukrainian or belonged to other local ethnic groups. It is worth emphasizing, however, that the Russians remain a northern people by origin and traditions, and that the extreme north of the country is their ethnic heartland.
Before the creation of the Russian Empire, Russian territory included a number of independent and semi-independent princedoms and republics—Novgorod, Pskov, Tver, and others. During the history of the empire, other Russian groups were formed in the outlying segments of the territory, from populations of runaway serfs and peasant migrants. These groups were distinguished in social status and organization from the peasants of the central Russian territory, and some of these distinctions, based in part also on religious differences, persist to this day.
The peasant population of the central Russian territory is marked by a strong sense of ethnic identity and separation from other groups, both Western European (predominantly Roman Catholic) and Eastern (predominantly Turkic and Muslim). The outlying Russian groups absorbed much of the culture of the people among whom they settled, however, and carried on extensive trade with them. Some groups of Russian religious dissidents, in fact, even crossed over into Romanian, Turkish, or Chinese territory.