Recent studies by Alan Tyson (paper) and Wolfgang Plath (handwriting) reveal that Mozart’s E-major Horn Concerto, K. 447, probably originated in 1787, the year that witnessed the composition of Don Giovanni, and not in 1783 as was long thought to be the case. Even in its new chronology it remains the third of Mozart’s completed horn concertos. It is uncertain why he failed to enter it in his autograph catalogue of works. Assuming that this was not a simple oversight, the reason may be that he wrote the piece as a gesture of friendship for the horn player Joseph Leutgeb (1732–1811) and perhaps did not consider it especially significant. Mozart was fond of pulling pranks on his friend Leutgeb. A relatively harmless instance can be found in the finale, where Leutgeb is twice mentioned by name in the score, with “Leutgeb” appearing instead of “Solo.” The passages in the first movement where the soloist plays along with the tutti may be a similar prank. Musically, they are quite superfluous and were probably intended as warming-up exercises.
The four horn concertos register Leutgeb’s declining command of his instrument as he grew older. While the first two (K. 417 and K. 495) have an ambitus extending to written c³, Mozart restricted the compass of the third to some two octaves, from g to a². In the final concerto (K. 412) the ambitus is even reduced to a ninth, from g¹ to a². Today’s performers would do well not to go beyond Mozart’s prescribed ambitus when playing their cadenzas. Those suggested by Robert D. Levin in the appendix of the horn part are exemplary in this respect; they can be found in the edition for horn and piano (HN 703 and EB 10703) that belongs to the present score.
Interestingly, the Romance has also come down to us in a different version for horn and strings attributed to Michael Haydn and published in 1802.¹ While the accompaniment parts have nothing in common with the original, the horn part quotes the Romance theme only to depart gradually from Mozart’s original. Karsten Nottelmann recently speculated that Leutgeb had other composers orchestrate, supplement and correct his own works. This would explain not only the two versions of the Romance, but also the two versions of the Rondo K. 412 and 514 – as a Mozart fragment and as a work by Franz Xaver Süssmayr.²
The source tradition of this concerto is virtually ideal. The generally clearly legible autograph score has survived fully intact and is preserved in the British Library in London (shelf mark Zweig MS. 55). It consists of eleven leaves containing twenty-two written pages in oblong format. Mozart began his foliation afresh at the Romance, which suggests that he initially composed the middle and the final movements and only added the opening movement later. Particularly noteworthy is the fact that Mozart had originally intended to set two horns in E flat instead of the bassoons in the first movement.
The present score, just as the aforementioned edition for horn and piano, is based on the autograph, which is the sole source. We have refrained from making the distinction – often not unequivocal – among the signs notated in a continuum between (staccato) dots and dashes; instead, dashes have been uniformly set.³ Since Mozart generally leaves the horn parts nearly unmarked, regardless whether the horn is used as a solo or tutti instrument, our edition limits itself to a few careful additions made by the editor in the horn part at parallel passages in the same key. Editorial additions are signalized by parentheses, slurs by broken lines.
The editor wishes to extend his warm thanks to the British Library in London for allowing him to consult the source both in the original and in microfilm. I also thank Ernst-Günter Heinemann, Christian Rudolf Riedel and Ab Koster for helping me with the publication of this volume.

Munich, Autumn 2013

1) MH 806, see Charles H. Sherman / T. Donley Thomas, Johann Michael Haydn (1737–1806), a chronological thematic catalogue of his works, Stuyvesant, NY 1993.
2) Karsten Nottelmann, Die Solo gab Leitgeb dazu. Neues zu Mozarts Hornkonzerten, in: Acta Mozartiana. vol. 59 (2012), no. 2, pp. 123–136.
3) See: Clive Brown, Dots and Strokes in Late 18th- and 19th-Century Music, in: Early Music. vol. 21 (1993), no. 4, pp. 593–610 and Robert Riggs, Mozart’s Notation of Staccato Articulation: A New Appraisal, in: The Journal of Musicology. vol. 15 (1997), no. 2, pp. 230–277. The distinction between (staccato) dots and dashes had been kept in the first printing of the edition for horn and piano of HN 703 published by Henle Verlag in Munich in 2000.