Bach (bäKH, bäk) German composer and organist of the late baroque period. Among the greatest composers in history, he wrote more than 200 cantatas, the Saint Matthew Passion (1729), the Mass in B minor (1733-1738), orchestral works such as the six Brandenburg Concertos, and numerous works for organ, harpsichord, other solo instruments, and chamber ensembles. Four of his children became noted musicians: Wilhelm Friedemann Bach (1710-1784); Carl Philipp Emanuel Bach (1714-1788), an important figure in the development of the symphony; Johann Christoph Friedrich Bach (1732-1795); and Johann Christian Bach (1735-1782).