Frédéric Chopin – Impromptu No. 4 Op. 66
Frédéric Chopin’s Fantaisie-Impromptu (Polish: Fantazja-Impromptu) in C♯ minor Op. posth. 66 is a solo piano composition. It was composed in 1834 and published posthumously in 1855 despite Chopin’s instruction that none of his unpublished manuscripts be published. The Fantaisie-Impromptu is one of Chopin’s most frequently performed and popular compositions.
The Fantaisie-Impromptu was written in 1834, as were the Four Mazurkas (Op. 17) and the Grande valse brillante in E♭ major (Op. 18), but unlike these other works, Chopin never published the Fantaisie-Impromptu. Instead, Julian Fontana published it posthumously, along with other waltzes Opp. 69 and 70. It is unknown why Chopin did not release the Fantaisie-Impromptu. James Huneker called parts of it “mawkish” and “without nobility”. Ernst Oster conducted a technical examination of the piece which hints at similarities between the Fantaisie-Impromptu and Ludwig van Beethoven’s “Moonlight” Sonata (Quasi una fantasia), which he cites as the reason for Chopin’s reluctance to publish the piece.
The mystery may have been solved in 1960 when pianist Arthur Rubinstein acquired the “Album of the Baroness d’Este” which had been sold at auction in Paris. The album contained a manuscript of the Fantaisie-Impromptu in Chopin’s own hand, dated 1835, stating on the title page in French “Composed for the Baroness d’Este by Frédéric Chopin”. The facts of its authenticity having been “guaranteed by the French authorities” and that it shows “a delicate care for detail” and “many improvements in harmony and style” in comparison to the previously published version, Rubinstein considered absolute proof that it is the finished work. In his preface to the “Rubinstein Edition”, published by G. Schirmer, Inc. in 1962, Rubinstein surmises that the words “Composed for” in place of a dedication imply that Chopin received a paid commission for the work, so he had actually sold it to the Baroness.