Vitim campaign of M. Perfiryev, 1639 and the first Russian attempts to penetrate to the Amur

The article discusses and analyzes the official letter («otpiska») of the first Yakut voivodes Petr Golovin and Matvej Glebov, which was contained detailed and truthful information about the path to the river Shilka, received by group Yenisei service people led by famous explorer Maxim Perfiryev. As a result of the undertaken campaign upwards on the river Vitim inhabitants of Yeniseisk was possible to reconnoitre a way in earlier unknown populous earths («zemlitsy») that soon gave rise to move troops of Yakut service people in the Amur River basin.