The work of G.K. Kotoshikhin is one of the most valuable sources about the state of the Moscow state in the middle of the 17th century. Its author, Grigory Karpovich Kotoshikhin, was a clerk of the Ambassadorial order. In 1664 he fled from Muscovy to Poland. After spending some time in Poland, he gave advice on the defense capabilities of Muscovy, and then moved to Prussia and further to Lubeck and Sweden. In the years 1666-1667. he lived in Stockholm under the name of Ivan Alexander Selitsky, where, "with the encouragement" of State Chancellor Count Magnus Delagardi, he compiled his description of the life, customs and political structure of Russia. In 1667 Kotoshikhin was accused of murdering his householder and executed.