Keyboard concertos by Johann Sebastian Bach soloists, were all adapted into harpsichord concertos by the composer, BWV 1058, 1054 and 1062 respectively. It is often assumed that Bach's extant violin concertos were written in his Köthen period (1717–1723): it can however not be proven from documentary evidence that any of them existed prior to around 1730. In September 1725 Bach performed organ music, accompanied by other instruments, in Dresden. The works he performed there have not been identified. More than a year later he composed several cantatas with an organ obligato part. Several movements of such cantatas were derived from earlier lost concertos, and resurfaced in
Organ concertos, Op. 4 (Handel) In November and December 1734, Handel presented various opera revivals and a newly composed opera-ballet "Terpsichore". However the combination of dance and opera seria was not sufficient to attract the opera going public. In January 1735 Ariodante opened, but, despite the quality of the music and a visible royal presence, was no more successful. It was in March that Handel started his first oratorio season, featuring the organ concertos HWV 290-293. The timing of the performances avoided conflicts with events in other London theatres and the local papers advertised the "new Concertos on the Organ." In spite of this his