Russian author, librettist and translator (b. 14/26 December 1823; d. 1890), born Konstantin Ivanovich Zvantsev (Константин Иванович Званцев).
Zvantsev was a music and theatre critic for the journal Art (Искусство), and the author of translations of Wagner's operas Tannhäuser and Lohengrin. Some early writers (including Modest Tchaikovsky) mistakenly credit Zvantsev with translating the story on which Tchaikovsky's opera Iolanta (1891) was based.
Correspondence with Tchaikovsky
One letter from Tchaikovsky to Konstantin Zvantsev has survived, dating from 1876, and has been translated into English on this website:
One letter from Zvantsev to Tchaikovsky, dating from 1888, is preserved in the Klin House-Museum Archive.