Over four years separate this short two-movement sonata from its predecessor, Les Adieux, Op. 81a. These years saw the creation of the Seventh and Eighth Symphonies, the Archduke piano trio, Violin Sonata No. 10 and the overtures to Egmont and Fidelio, among other works, but none for piano solo. The sonata was dedicated to Beethoven's friend and patron Count Moritz von Lichnowsky, and was for a long time believed to contain an extra-musical narrative, similar to Les Adieux - namely the story of the count's marriage to the opera singer Josepha Stummer, after the death of his first wife, against the wishes of his family.
This belief was based on an entry in Beethoven's conversation book dating from 1823, in which his part-time secretary Anton Schindler noted that 'Lichnowsky played the Sonata, Op. 90 containing the story of his marriage.' In later years Schindler elaborated on the story, writing that upon being questioned by Count Lichnowsky about the idea behind the music, Beethoven burst out laughing and told him it was the love story between the count and his wife. The first movement, he suggested, could be titled 'Struggle between mind and heart' and the second 'Conversations with the beloved'. Today we know that the original entry from 1823 was falsified by Schindler, and the entire story has likely been fabricated to support his claim that Beethoven often used 'poetic ideas' as inspiration for his music. The timeline doesn't quite fit either, as the marriage between the count and the singer didn't take place until 1820. But it is not inconceivable that there was some truth behind the story, as in summer 1814 - around the time of the sonata's composition - the illegitimate daughter of the count and the singer was born, so Beethoven might have known about the liaison by then.
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