Prelude and Fugue in C sharp minor

from The Well-Tempered Clavier Book 1 (before 1722)

While it would be an exaggeration to claim that all piano preludes derive ultimately from Bach’s Well-Tempered Clavier, there is no doubt that the composers of the more significant sets of preludes in the piano repertoire were very aware of Bach’s example. Even Debussy - who, unlike Chopin and Rachmaninov, had no interest in covering all the major and minor keys - was not satisfied until he had completed a set of twenty-four such pieces. As for the concept that a prelude doesn’t necessarily have to precede anything, while Chopin was the first to make a deliberate point of it and demonstrate it in twelve different key, it wasn’t entirely alien to Bach’s thinking either.

The present Prelude in C sharp minor, for example, is one of eleven from the Well-Tempered Clavier that appear in the Clavier-Büchlein without their accompanying Fugues. Besides, like most of its companions, it has nothing in common with the following Fugue apart from its tonality. The Prelude, though polyphonic in texture, is a lyrical, distinctly vocal arioso. The Fugue, on the other hand, is a fundamentally instrumental, intellectually challenging composition in now fewer than five contrapuntal voices based on not only the lapidary theme with which it begins but on two other, mutually contrasting themes as well. It is perhaps the most complex Fugue in all the Forty-Eight.