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-Prussia broke out, with Brandenburg-Prussia involved as an ally of the Dutch Republic. This alliance was based on a treaty of 1669, and resulted in French occupation of Brandenburg-Prussian Cleves. In June 1673, Frederick William abandoned the Dutch alliance and concluded a subsidy treaty with France, who in return withdrew from Cleves. When the Holy Roman Empire declared war on France, a so-called "Reichskrieg", Brandenburg-Prussia again changed sides and joined the imperial forces. France pressured her ally Sweden to relieve her by attacking Brandenburg-Prussia from the north. Charles XI of Sweden, dependent on French subsidies, reluctantly occupied the Brandenburgian Uckermark in