[1] Hydronymics indicate the ancient presence of the Balts in two regions that were occupied by the East Slavs at the beginning of historical time: The discovery of obvious hydronymic Baltisms in the Middle Volga region has brought to the fore the problem of the eastern boundary of the Balts' settlement.

Vladimir Napolskikh considers the Imenkovo ​​culture of the Middle Volga region to be the eastern flank of the Balto-Slavic cultural and linguistic community,[2] although this view is highly controversial.

[3] According to Péter Hajdu, the early contacts of the Volga Finns with the Balts, on the one hand, and the ancestors of the Indo-Iranians, on the other, spatially belong to the Middle Volga region, and in time - to the common Finnish era between the beginning of the 1st millennium BC and the 6th-8th centuries AD.

In the first centuries of our era, the territory described above was occupied by the Dnieper-Dvina (in the west) and Moshchiny (in the east) cultures, which are usually associated with the Dnieper Balts.

Relics of the Moshchiny culture were preserved until the 11th-12th centuries in the north of its area, where the Eastern Galindians lived according to chronicle data.