Iolanta, Op. 69, (Russian: Иоланта) is a lyric opera in one act by Pyotr Tchaikovsky. It was the last opera he composed. The libretto was written by the composer's brother Modest Tchaikovsky, and is based on the Danish play Kong Renés Datter (King René's Daughter) by Henrik Hertz, a romanticised account of the life of Yolande de Bar. In the original Danish play, the spelling of the princess's name was "Iolanthe", later adopted for the otherwise unrelated Gilbert and Sullivan operetta of that name. The play was translated by Fyodor Miller and adapted by Vladimir Zotov. The opera received its premiere on 18 December 1892 in Saint Petersburg.
Composed after the completion of The Queen of Spades, Tchaikovsky worried that he had lost his creative inspiration after such a large project. He started Iolanta with the final duet in June 1891, and despite his worries, finished composition in September and orchestration in November. The public reception was quite favorable, though Tchaikovsky was disappointed and felt he was repeating himself, especially when compared to his earlier work, The Enchantress.
Me involvunt tenebrae cum lux paulatim evanescat.
Obrigescunt formae et nox regnum suum celebrat.
Anima mae signum cerae occultorum sinu totae claritatis secre-
torum scindit...
Incipit lectio tenebrarum.