sentences:  According to Russian archaeologists, prior to about the second half of the 7th century AD the Lesser Khingan mountain range formed a natural boundary between two groups of archaeological cultures.West of the range, the Talakan Culture (талаканская культура) was succeeded by the Mikhailovskaya Culture (михайловская культура), which has been identified with the Mongolic-speaking Shiwei people.East of the range, the Poltsevo Culture (польцевская культура) and the Naifeld Group (найфельдская группы, also known as Tongzhen Culture based on the findings on the Chinese side of the River) of the Mohe Culture was found; the latter was identified with the Tungusic Heishui Mohe people.