Brandenburg Concerto No. 5 "Brandenburg Concertos" takes a central place. Nonetheless around half a dozen of Bach's extant concertos, including some of the "Brandenburg Concertos" and lost models of his later harpsichord concertos, seem to have had their roots in his Weimar period. Most of what Bach may have left with his employer in Weimar perished in a fire destroying Schloss Weimar in the 1770s. In 1719 a new large two-manual harpsichord arrived in the residence of Bach's then-time employer at Köthen. BWV 1050a, an extant early version of the fifth "Brandenburg Concerto", may have been conceived for this instrument, but that seems unlikely
Brandenburg Concertos of a trio sonata for two violas and continuo, although the cello has a decorated version of the continuo bass line. In the last movement, the spirit of the gigue underlies everything, as it did in the finale of the fifth concerto. Because King Frederick William I of Prussia was not a significant patron of the arts, Christian Ludwig seems to have lacked the musicians in his Berlin ensemble to perform the concertos. The full score was left unused in the Margrave's library until his death in 1734, when it was sold for 24 groschen (as of 2014, about US$24)