Bach, Johann Sebastian

German composer. A master of counterpoint, his music represents the final stage of the baroque polyphonic style. His orchestral music includes the six Brandenburg Concertos (1721), other concertos for keyboard instrument and violin, four orchestral suites, sonatas for various instruments, three partitas and three sonatas for violin solo, and six unaccompanied cello suites. Bach's keyboard music, for clavier and organ, his fugues, and his choral music are of equal importance.

His appointments included positions at the courts of Weimar and Anhalt-Cöthen, and from 1723 until his death he was musical director at St Thomas's choir school in Leipzig.

He married twice and had over 20 children (although several died in infancy). His second wife, Anna Magdalena Wilcken, was a soprano; she also worked for him when his sight failed in later years.

Although he was not always appreciated by other musicians of his day, Bach's place in music history was aptly summed up by his first major biographer, Johann Nikolaus Forkel (1749–1818), in his book Über Johann Sebastian Bachs Leben, Kunst, und Kunstwerke (1802; English translation 1820 and 1920): ‘He is the river, to which all other composers are tributaries’.