P. Beketov's official letter («Otpiska») from the mouth of the Olekma river (about Russian-Tunguss relations on the Middle Lena in the mid 30s of the 17th century)

The published document is a source, eloquently demonstrates the complexity of the relations between Russian service and industrial people with the aboriginal population on the territory, which is in the process of its subordination to the authority of the Russian administration. Abuse and ill-considered actions of the service people led to mistrust and upsurge of resistance of the Tungus.