In a 2014 journal article for Russian History, The Baltic Finnic People in the Medieval and Pre-Modern Eastern European Slave Trade, author Jukka Korpela looks at the routes of the slave trade in Eastern Europe. Jukka is affiliated with the Department of Geographical and Historical Studies, University of Eastern Finland.
Raids and the kidnapping of humans in East Europe together with a late medieval and pre-modern Black Sea slave trade are well known in the scholarly literature. This kind of slave trade also extended via the Volga to Caspia and Central Asia. Besides young male slaves, there was a market for small blond boys and girls in both regions, where they were expensive luxury items. Gangs from the Volga, at least, launched raids towards the north, and it is possible that the northern kidnapping raids and the transportation of prisoners from the northern forests to Novgorod were also connected with the southern slave trade.