Thereupon Russian colonization and political influence retreated northwards, and from that time the continuous stream of Russian history is to be sought in the land where the Vikings first settled and in the adjoining basin of the upper Volga.
These are, as has been said, almost exclusively the chronicles of the lands visited by the vikings.
You can't just lop someone's head off and blame it on the Vikings.
William Phillips on page 63 states that the major component of slave trade in the eleventh century were the Vikings.
Vikings etc do it in the movies all the time - they must have had very active coopers!