The Incidental music to Masquerade was written in 1941 by Aram Khachaturian for a production of a play of the same name by Russian poet and playwright Mikhail Lermontov. It premiered on 21 June 1941 in the Vakhtangov Theatre in Moscow. It is better known in the form of a five-movement suite.

Khachaturian was asked to write music for a production of Masquerade being produced by the director Ruben Simonov. The famous waltz theme in particular gave Khachaturian much trouble in its creation: moved by the words of the play's heroine, Nina - "How beautiful the new waltz is! ...something between sorrow and joy gripped my heart." - the composer struggled to "find a theme that I considered beautiful and new". His former teacher, Nikolai Myaskovsky, attempted to help Khachaturian by giving him a collection of romances and waltzes from Lermontov's time; though these did not give immediate inspiration, Khachaturian admitted that "had it not been for the strenuous search" for the appropriate style and melodic inspiration, he would not have discovered the second theme of his waltz which acted "like a magic link, allowing me to pull out the whole chain. The rest of the waltz came to me easily, with no trouble at all." (Wikipedia)

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