https://en.wikipedia.org/wiki/Serfdom_in_Russia

Serfdom became the dominant form of relation between Russian peasants and nobility in the 17th century.

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Note added at 4 mins (2020-09-24 12:51:36 GMT)
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Slaves and serfs
As a whole, serfdom both came and remained in Russia much later than in other European countries. Slavery remained a legally recognized institution in Russia until 1723, when Peter the Great converted the household slaves into house serfs. Russian agricultural slaves were formally converted into serfs earlier in 1679.[10][11]

Formal conversion to serf status and the later ban on the sale of serfs without a land did not stop the trade in household slaves; this trade merely changed its name. The private owners of the serfs regarded the law as a mere formality. Instead of "sale of a peasant" the papers would advertise "servant for hire" or similar.