Keyboard concertos by Johann Sebastian Bach the harpsichord concertos BWV 1052, 1053 and 1059. Based on harpsichord concertos and earlier cantata movements orchestral organ concertos were reconstructed and/or transcribed and arranged. The parts from the Concerto for four harpsichords BWV 1065 (Bach's arrangement of the Concerto for Four Violins, RV 580, by Antonio Vivaldi), have been dated to around 1730. Whereas the concertos with a single harpsichord soloist were composed partly to showcase Bach's own prowess at the keyboard, the others were written for different purposes, one of them being as —music for domestic performance within the Bach household at the Thomaschule in Leipzig. Johann Nikolaus
Brandenburg with Poland. Brandenburg originated in the Northern March in the 900s AD from areas conquered from the Wends, and later became the Margraviate of Brandenburg, a major principality of the Holy Roman Empire, with Albert the Bear as prince-elector. In the 17th century Brandenburg came under the rule of the House of Hohenzollern, the rulers of Prussia, who established Brandenburg-Prussia to become the core of the Kingdom of Prussia. Brandenburg became the Province of Brandenburg in 1815, a province within the kingdom and later within the Free State of Prussia. Brandenburg was established as a state in 1945 after World