BWV
The Bach-Werke-Verzeichnis (BWV; Bach-Works-Catalogue) is a catalogue of compositions by Johann Sebastian Bach. It was first published in 1950, edited by Wolfgang Schmieder. The catalogue's second edition appeared in 1990. An abbreviated version of that second edition, known as BWV2a, was published in 1998.
1126 compositions were assigned a BWV number in the 20th century. More compositions were added to the catalogue in the 21st century. The Anhang (Anh.; Annex) of the BWV lists over 200 lost, doubtful and spurious compositions.
The first edition of the Bach-Werke-Verzeichnis was published in 1950. It allocated a unique number to every known composition by Bach. Wolfgang Schmieder, the editor of that catalogue, grouped the compositions by genre, largely following the 19th-century Bach Gesellschaft (BG) edition for the collation (e.g. BG cantata number = BWV number of the cantata):
The Anhang of the BWV listed works that were not suitable for the main catalogue, in three sections:
Within each section of the Anhang the works are sorted by genre, following the same sequence of genres as the main catalogue.
Schmieder published the BWV's second edition in 1990, with some modifications regarding authenticity discriminations, and more works added to the main catalogue and the Anhang. Several compositions were repositioned in the over-all structure of chapters organised by genre and Anhang sections. In 1998 Alfred Dürr and Yoshitake Kobayashi published a small edition of the catalogue, based on the 1990 second edition. This edition, known as BWV2a, contained a few further updates and collation rearrangements.
New additions (Nachträge) to BWV2/BWV2a included:
An upper case R was used as an addition to a BWV number to indicate a reconstructed version, that is a conjectured earlier version of a known composition.
Numbers above BWV 1126 were added in the 21st century.
The numbers assigned to compositions by Johann Sebastian Bach and by others in the Bach-Werke-Verzeichnis are widely used for the unique identification of these compositions.
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