In the northern part of Byelorussia (Vitebsk District), before the formation of Kiev state, complicated ethnic processes took place and in a course of them Krivichi of Polotsk (Polocanai) - the Western branch of Krivichi, which settled in the Northern Byelorussia in the second half of the First Millenium, - were formed. The ethnic dependence of polocanai is a part of the general problem of formation of Krivichi.
The ethnogenesis of Krivichi of Polotsk consists of three stages, which are obtained in monuments of the Long Barrow Culture. The characteristic feature of the first stage (the 5th - the early 8th centuries) is ceramics of Bantserovo-Tushemlya type, the characteristic feature of the second stage (the 8th-I0th centuries) - long barrows of "Smolensk-Polotsk" type with cremated graves (Fig. 1-3). The third stage (the 11 th -12 th centuries) is notable for a formation of the culture of barrows of Eastern Slavs with barrows, having round earth piles and non-cremated graves, on the base of Baltic substratum. These indigenes are referred to as Krivichi or Polocanai in written sources and are reckoned among the founders of the pro-Byelorussian ethnosis. Krivichi of Polotsk had well-fortified settlements, such as Polotsk, Vitebsk, Lukoml, which became a base of a formation of towns of Krivichi of Polotsk and finally (in the 9th-13th centuries) - Polotsk Principality.
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