Franz Schubert

Schubert did not himself invent the title "Impromptu"; the Bohemian composer Jan Vorisek had published the first set of works called Impromptus in 1822 in Vienna, works which Schubert certainly knew. Written in the lighter and less demanding style popular at the time, Vorisek's Impromptus proved both popular and, in their simple ternary structure and less virtuosic piano writing, capable of imitation.

Schubert's first set of four Impromptus were composed in 1827 between the two halves of Winterreise and something of those songs' darkness and tragedy can be found in the piano pieces as well. The first Impromptu, Op. 90, No. 1, (D. 899.1) in C minor is in ternary form with a harsh and march-like theme in the outer sections in C minor alternating with a warmer and more flowing theme in A flat major in the central section. Schubert expands the work's ternary structure with a large-scale development after the central section and he enlarges the harmonic scheme with modulations to keys as distant as the flat dominant major and the flat supertonic minor. Through this structural expansion and harmonic nuances, Schubert intensifies the C minor Impromptu's emotional content almost to the point of being unbearable. The work's long coda's alternation between the tonic major and minor closes in the major, but it is a major so compromised by the minor that the final cadence seems more resigned than consoled.