Keyboard concertos by Johann Sebastian Bach left Weimar in 1717. Many of Bach's orchestral harpsichord concertos are adapted from a model with one or more violin solo parts. Several of these earlier models are extant. The oldest of these is Vivaldi's concerto for four violins, RV 580, published in 1711, model for Bach's concerto for four harpsichords, BWV 1065. Bach replaced the part of his fourth "Brandenburg Concerto", BWV 1049, composed in 1721 or earlier, by a harpsichord part when he reworked it to the harpsichord concerto BWV 1057. Bach's extant violin concertos BWV 1041–1043, two for a single violin soloist and one for two violin
Oberliga Berlin-Brandenburg each who would determine their champions in a home-and-away format. The two divisional champions would then play for the Brandenburg championship in a two-game series. Should each team win one game, a third game was held as a decider. The Brandenburg champion would then continue on to play in the German football championship. From 1925 onwards, the runners-up of Brandenburg was also qualified for an enlarged national championship. Below the league, as the second division in Brandenburg, four "Kreisligas" were set, those being: From 1925 onwards, until 1931, the league was dominated by Hertha BSC Berlin, who won it every