In the decades after Mozart's death in 1791 there were several attempts to catalogue his compositions, for example by
Franz Gleißner and
Johann Anton André (published in 1833), but it was not until 1862 that Ludwig von Köchel succeeded in producing a comprehensive listing. Köchel's 551-page catalogue was titled (
Chronological-thematic Catalogue of the Complete Musical Works of W. A. Mozart). Köchel attempted to arrange the works in chronological order, but many compositions written before 1784 could only be estimated, although
Leopold Mozart had compiled a partial list of his son's earlier works; Mozart's
catalogue of his own compositions (begun in February 1784 with
K. 449) allows relatively precise dating of many of his later works. The catalogue included the opening bars of each piece, known as an
incipit. Köchel divided the corpus into a main chronology of 626 works, and five appendices ( in German), abbreviated Anh. I–V which comprise: • I – Lost authentic works • II – Fragments by Mozart • III – Works by Mozart transcribed by others • IV – Doubtful works • V – Misattributed works Since Köchel published his original catalogue in 1863 (now referred to as K), the dating of Mozart's compositions has been subject to constant revision. Many more pieces have since been found, re-dated, re-attributed and re-numbered, requiring three revised editions of the catalogue. Subsequent editions – especially the third edition (K) by
Alfred Einstein (1937), and the sixth edition (K) by
Franz Giegling, , and (1964) – have reflected attempts to arrange the growing list of works in a more accurate chronological order, according to various levels of scholarship. Because of the confusing renumbering between versions, the ninth edition (K) by
Neal Zaslaw (2024) abandoned the chronological order: all works in the main body of the catalogue that were included in a previous edition return to the oldest number they were given, and works newly included in the ninth edition were given numbers past 626, all the way to 721. A major shortcoming of K was that there was no room to expand the strictly sequential numbering in the main catalogue to allow for any new discoveries or further reassessment of existing works. For the 1937 edition (K) Einstein (following the analyses of
Théodore de Wyzewa and Georges de St. Foix) reassigned some works from the original K appendices into the main catalogue by interpolating numbers with a lower-case letter suffix. In K some of these were, per intervening scholarship, returned to re-structured appendices: • K. 626a • K. 626a I – 64
Cadenzas by Mozart to his own keyboard concertos • K. 626a II – Cadenzas by Mozart to keyboard concertos by other composers • K. 626b – 42 sketches & other fragments by Mozart (replacing K Anh. II) • Anh. A – Copies by Mozart of other composers' works • Anh. B – Works by Mozart transcribed by others • Anh. C – Doubtful and misattributed vocal (C 1–10) and instrumental (C 11-30) works For example,
Divertimento for Wind Octet in E was renumbered multiple times: • It was numbered K. Anh. 226 in K; • Einstein placed it in the K main catalogue as K. 196e, between K. 196 and K. 197; • K reassigned it again to the 'doubtful' appendix C as K. Anh. C 17.01; • K reverted to Einstein's assignment as K. 196e (though it is still considered a doubtful work). Some works in Anh. A have been identified since 1965 as by Leopold Mozart. Many works in Anh. C have since been more reliably assigned to other composers, or to Mozart himself. ==List of existing Mozart compositions==