Bach "composed" the 5 concertos for organ in the years 1713 and 1714, when he was employed by the Weimar court. Making transcriptions of other people's scores was then normal musical practice. In this way Bach has rewritten various violin concertos by Vivaldi in particular for the sound possibilities of the organ or the harpsichord. 3 concertos of the share for organ were written after Vivaldi and
… 2 after Johann Ernst von Saxen-Weimar, a nephew of Bach's patron. Precisely because the translation to the idiom of the organ reveals specific sound possibilities, these types of operations place high demands on the player. The French organist Francois-Henri, pupil of Pierre Cochereau and Michel Chapuis, among others, mastered this matter effortlessly, without lapsing into a dry virtuosity. (H.more
