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 the Province of Brandenburg, again subdivided into the government regions of Frankfurt and Potsdam. In 1881, the City of Berlin was separated from the Province of Brandenburg. However, industrial towns ringing Berlin lay within Brandenburg, and the growth of the region's industrial economy brought an increase in the population of the province. The Province of Brandenburg had an area of and a population of 2.6 million (1925). After World War II, the Neumark, the part of Brandenburg east of the Oder–Neisse line, was transferred to Poland; and its native German population expelled. The remainder of the province became a state