Wilhelm Friedemann Bach (22 November 1710 – 1 July 1784), the second child and eldest son of Johann Sebastian Bach and Maria Barbara Bach, was a German composer and performer. Despite his acknowledged genius as an organist, improviser and composer, his income and employment were unstable and he died in poverty.
Wilhelm Friedemann (hereafter Friedemann) was born in Weimar, where his father was employed as organist and chamber musician to the Duke of Saxe-Weimar. In July 1720, when Friedemann was nine, his mother Maria Barbara Bach died suddenly; Johann Sebastian Bach remarried in December 1721. J. S. Bach supervised Friedemann's musical education and career with great attention. The graded course of keyboard studies and composition that J. S. Bach provided is documented in the Clavier-Büchlein vor Wilhelm Friedemann Bach (modern spelling: Klavierbüchlein für Wilhelm Friedemann Bach), with entries by both father and son. This education also included (parts of) the French Suites, (Two-Part) Inventions, (Three-Part) Sinfonias (popularly known as "Inventions"), the first volume of The Well-Tempered Clavier, and the six Trio Sonatas for organ. At the age of 16 he went to Merseburg to learn the violin with his teacher Johann Gottlieb Graun.
In addition to his musical training, Friedemann received formal schooling beginning in Weimar. When J.S. Bach took the post of Cantor of the St. Thomas Church in Leipzig (in 1723), he enrolled Friedemann in the associated Thomasschule. (J.S. Bach—who had himself been orphaned at the age of 10—said that he took the position in Leipzig partly because of the educational opportunities it afforded his children). On graduating in 1729, Friedemann enrolled as a law student in Leipzig University, a renowned institution at the time, but later moved on to study law and mathematics at the University of Halle. He maintained a lifelong interest in mathematics, and continued to study it privately during his first job in Dresden.