organist at the St. Catherine's church. Then he moved to Berlin, where he initially was welcomed by the princess Anna Amalia (the sister of Frederick the Great). Later, no longer in favor at court, he gave harpsichord lessons to Sarah Itzig Levy, the daughter of a prominent Jewish family in Berlin and an avid collector of Bach and other early 18th century music, who was also a "patron" of Friedemann's brother CPE Bach. Friedemann died in Berlin. Earlier biographers have concluded that his "wayward" and difficult personality reduced his ability to gain and hold secure employment, but the scholar David Schulenberg writes (in the Oxford Composer Companion: J.S. Bach, ed. Malcolm Boyd, 1999) that "he may also have been affected by changing social conditions that made it difficult for a self-possessed virtuoso to succeed in a church- or court-related position" (p. 39). Schulenberg adds, "he was evidently less willing than most younger contemporaries to compose fashionable, readily accessible music". Friedemann Bach was renowned for his improvisatory skills. It is speculated that when in Leipzig his father's accomplishments set so high a bar that he focused on improvisation rather than composition. Evidence adduced for this speculation includes the fact that his compositional output increased in Dresden and Halle. Friedemann's compositions include many church cantatas and instrumental works, of which the most notable are the fugues, polonaises and fantasias for clavier, and the duets for two flutes. He incorporated more elements of the contrapuntal style learned from his father than any of his three composer brothers, but his use of the style has an individualistic and improvisatory edge which endeared his work to musicians of the late 19th century, when there was something of a revival of his reputation. Friedemann's students included Johann Nikolaus Forkel, who in 1802 published the first biography of Johann Sebastian Bach; Friedemann, as well as his younger brother Carl Philipp Emanuel Bach, were major informants for Forkel. Friedemann has in earlier biographies been called a poor custodian of his father's musical manuscripts, many of which he inherited; however, more recent scholars are uncertain how many were lost. It is known that Friedemann sold some of his father's collection to raise cash to pay debts (including a large sale in 1759 to Johann Georg Nacke). Also, his daughter took some of the Sebastian Bach manuscripts with her when she moved to America, and these were passed on to