Bach Gesellschaft (Bach Society). Ger. soc. founded 1850 to commemorate the centenary of the death of J. S. Bach by publishing complete critical edn. of his works based mainly on the coll. of his MSS in Berlin. The project, urged by Robert Schumann in an article in the Neue Zeitschrift für Musik (xix, 87), was executed by Otto Jahn in assoc. with Schumann, Carl Friedrich Becker, Moritz Hauptmann, and the publishing firm of Breitkopf und Härtel. Issued 46 annual publications in 59 vols. between 1850 and 1900. The achievement was a vast feat of scholarship but, understandably, not without error. Some works definitely or probably not by Bach were incl.

With publication of the concluding volume on 27 Jan. 1900 the Society was wound up and the Neue Bach Gesellschaft founded under the presidency of Herman Kretzschmar, Prof. at Leipzig Univ. Its objective was to publish Bach's mus. in practicable performing scores and to popularize it throughout Ger. by Bach fests. In 1904 the soc. began issue of a Jahrbuch (Yearbook), in which the latest Bach research is pubd., and in 1907 bought Bach's birthplace at Eisenach and made it a museum.

A Bach Soc. was founded in London 1849 to collect a library of Bach's comps. either printed or in MS. Under its auspices took place the first Eng. perfs. of St Matthew Passion (Hanover Sq. Rooms, London, 6 Apr. 1854) and Christmas Oratorio (London, 13 June 1864). 11 movements from the Mass in B minor were perf. on 24 July 1860. Soc. dissolved in Mar. 1870 and library given to RAM.