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
Brandenburg-Liga Brandenburg-Liga The Brandenburg-Liga (VI) ("formerly the Verbandsliga Brandenburg") is the highest league for football teams exclusively in the German state of Brandenburg and at step six of the German football league system. Until the introduction of the 3. Liga in 2008 it was the fifth tier of the league system, until the introduction of the Regionalligas in 1994 the fourth tier. The champions of the Brandenburg-Liga are directly promoted to the NOFV-Oberliga Nord. The Brandenburg-Liga, previously referred to as the "Verbandsliga Brandenburg", was established in 1990 from thirteen clubs as a highest league for the German state of Brandenburg, which