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
Brandenburg and the lands of the Hevelli from their last Wendish ruler, Pribislav, in 1150. After crushing a force of Sprevane who occupied the town of Brandenburg in the 1150s, Albert proclaimed himself ruler of the new Margraviate of Brandenburg. Albert, and his descendants the Ascanians, then made considerable progress in conquering, colonizing, Christianizing, and cultivating lands as far east as the Oder. Within this region, Slavic and German residents intermarried. During the 13th century, the Ascanians began acquiring territory east of the Oder, later known as the Neumark (see also Altmark). In 1320, the Brandenburg Ascanian line came to an