The Russian Federation (early Soviet Russia, RSFSR) is the historical heir but not legal successor of the Russian Empire, and the Russian Empire was not party to the Berne Convention (it was not country of Union for the protection of the rights of authors in their literary and artistic works), so according to article 5 of the Convention this work has no country of origin except:

• in the case of cinematographic work the maker of which has his headquarters or his habitual residence in a country of the Union, the country of origin shall be that country,
• in the case of of architecture erected in a country of the Union or other artistic works incorporated in a building or other structure located in a country of the Union, the country of origin shall be that country,
• in the case of other works if the author is a national of a country of the Union¹, the country of origin shall be that country.

¹ - Author who is not a national of a country of the Union but who has his habitual residence in a country of the Union, be assimilated to national of that country.

The exclusive rights to this work do not extend on territory of the Russian Federation according to article 1256 of the Civil Code of the Russian Federation (details), because this work does not meet the requirements on the territory of publication, on the author's nationality, and on obligations for international treaties.

The author died in 1769, so this work is in the public domain in its country of origin and other countries and areas where the copyright term is the author's life plus 100 years or fewer.