In 1899 he married Baroness de Rosen, and after 1900 he appeared but little in public; but he became better known as a composer, chiefly of pieces for his own instrument.
Von Rosen, Memoiren eines russischen Dekabristen (Leipzig, 1870).
Among critics of taste may be mentioned Nils Rosen von Rosenstein (1752-1824); the rhetorical bishop of Linkoping, Magnus Lehnberg (1758-1808); and Count Georg Adlersparre (1760-1809).
Rosen von Rosenstein embraced the principles of the encyclopaedists while he was attached to the Swedish embassy in Paris.
Vasilievski and Jernstedt, St Petersburg, 1896); Yahya of Antioch (contemporary Asiatic chronicle), extracts with Russian translation by Rosen (St Petersburg, 1883); Al Mekin (Elmacinus), Historia Saracenica (ed.