According to the 1988 sale catalogue, the sitter is believed to be the wife of Prince Nicolai Ivanovich Saltykov (1736-1816), Field Marshal, Minister of War, President of the Council of Ministers, Council of the Empire and the Senate, Governor of the Grand Dukes Alexander and Constantine Pavlovich of Russia.
For more information on Rockstuhl, see T. A. Selinova, Khudozhnik P. E. Rokshtul'. Iz istorii russkoi portretnoi miniatiury, Moscow, 2005.