Whilst serving as maestro di cappella in the city of Köthen , Johann Sebastian Bach composed the 24 preludes and fugues that form the Book I of The Well-Tempered Klavier. He had arrived in Köthen in 1717, shortly after his then employer, the Duke of Weimar, had lifted the punishment he had imposed upon Bach, releasing him from prison.
The Duke had an assortment of peculiarities which had been slowly but surely worsening his relationships with his "lackey" Bach (i.e. an assistant for various purposes), who had been serving him from 1708 as both chamber musician and organist of the Court. To the mix, we should add the rebellious character of konzertmeister Johann Sebastian, and his stubbornness and obstinacy, traits that accompanied him throughout his life, often hampering his dealings with his superiors.
In 1717, Bach learned that he had been recommended for the position of kapellmeister at the Court of Köthen, which he accepted with alacrity, sending at once his family to that city. Alas, he had not requested the mandatory authorization from the Duke...
When he did it, it was too late. Exasperated, the Duke did not respond and after Bach’s insistence, surely not very tactful, the boss lost his patience. After four weeks of imprisonment, Bach “was freed from arrest with notice of his unfavourable discharge”, as reads the note by the Registrar of the Court. Eventually, Bach reunited with his family in Köthen and took charge of his post, where he remained until 1723.
JS Bach - Prelude No. 2
This version of the Prelude No. 2 of The Well Tempered Klavier, Book 1, by Glenn Gould, is unmistakable. The Canadian pianist and composer renewed the interpretation of Bach (despite the fact that he used to play sitting at the piano on a short-legged chair, with his chin almost touching the keyboard!).