Op. 37 N° 2 G major
Prelude (6/8, Andante con moto, mezzo piano) Apr. 1837
Fugue (4/2, mezzo forte) 1837
Mendelssohn loved the organ and was a skilled organist. When he was 12 or 13 and already a pianist virtuoso, he started taking organ lessons with A.W. Bach (not linked to JSB!) and had numerous opportunities to play the organ when traveling in Germany or Switzerland.
Later, during his visits to Britain, he gave organ recitals (mostly improvising) : "His extempore playing is very diversified – the soft movements full of tenderness and expression, exquisitely beautiful and impassioned. In his loud preludes there are an endless variety of new ideas and the pedal passages so novel and independent as to take his auditor quite by surprise."
The three preludes and three fugues were composed at different times between 1830 and 1837 and published as "3 Preludes and Fugues" simultaneously by Novello in England and Breitkopf in Germany.
They are dedicated to Thomas Atwood, organist of St Paul's cathedral, whom he'd met in London in 1829. Atwood, who had been Mozart pupil when he was young, was 65 at that time and would die in 1838, shortly after the publication.