Overview
Johann Sebastian Bach's chorale harmonisations, alternatively named four-part chorales, are Lutheran hymn settings that characteristically conform to the following:
four-part harmony
SATB vocal forces
pre-existing hymn tune allotted to the soprano part
text treatment:
homophonic
no repetitions (i.e., each syllable of the hymn text is sung one time)
Around 400 of such chorale settings by Bach, mostly composed in the first four decades of the 18th century, are extant:
Around half of that number are chorales which were transmitted in the context of larger vocal works such as cantatas, motets, Passions and oratorios. A large part of these chorales are extant as autographs by the composer, and for nearly all of them a colla parte instrumental and/or continuo accompaniment are known.
All other four-part chorales exclusively survived in collections of short works, which include manuscripts and 18th-century prints. Apart from the Three Wedding Chorales collection (BWV 250–252), these are copies by other scribes and prints only published after the composer's death, lacking context information, such as instrumental accompaniment, for the individual harmonisations.
Apart from homophonic choral settings, Bach's Lutheran hymn harmonisations also appear as:
sung chorale fantasias in some of Bach's larger vocal works
hymn melodies for which Bach composed or improved a thorough bass accompaniment, for instance as included in Georg Christian Schemelli's Musicalisches Gesang-Buch
harmonisations included in purely instrumental compositions, most typically organ compositions such as chorale preludes or chorale partitas.
History
The compositions by Johann Sebastian Bach that had been printed during his lifetime were nearly exclusively instrumental works. Moreover, by the time Bach died in 1750 it was forgotten that a few of his vocal works (BWV 71, BWV 439–507,...) had indeed been printed in the first half of the 18th century. In the period between the publication of The Art of Fugue in the early 1750s, and the publication of further works from 1900, only one group of Bach's works was published: his four-part chorales.
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