Mozart’s C Minor Mass is one of the most significant masterpieces of choral music. But it only exists in fragmentary form. The new reconstruction by Ulrich Leisinger comes as close to an ideal version of the Mass as possible.
Hardly any other work by Wolfgang Amadé Mozart continues to exert such a fascination for connoisseurs and music lovers today as the C Minor Mass K. 427. It deserves admiration because of its monumentality and musical beauty, but it will always remain enveloped in the aura of the unfinished and the mysterious. What still remains unclear are the precise circumstances of its origin as a votive mass, the reasons for Mozart breaking off the composition, together with many details about the first performance; according to current knowledge this took place on 26 October 1783 in St. Peter in Salzburg. And yet the mass is at the same time a touching testimony of Mozart’s love for Constanze Weber, whom he married against his father’s wishes and for whom – if we interpret an entry in the diary of his sister Maria Anna, known as Nannerl, correctly – he wrote the soprano solos. The fact that although the mass remained a torso, it could be performed at all on Mozart’s last visit to Salzburg, is remarkable. With the C Minor Mass we have to deal with a fragment on several different levels: Mozart did not set all the sections of the ordinary of the mass: large sections of the Credo and the entire Agnus Dei are missing. In addition to this, parts of Mozart’s original manuscript were lost early on.
Recent Mozart scholarship has consistently focussed on the C Minor Mass, and in the process, some remarkable new discoveries have been made. At the time of its composition, Wolfgang Amadé Mozart evidently had access through Gottfried van Swieten to Johann Sebastian Bach’s Mass in B minor, a work which was an important compositional stimulus for him. The Kyrie, Gloria, Sanctus and Benedictus movements which were heard at the first performance are only found in a single early source. This copy of the score by Pater Matthäus Fischer is indeed based on the original Salzburg parts which ended up after Leopold Mozart’s death in the Holy Cross collegiate church of the Augustinian Canons in Augsburg. But it is an arrangement in which Fischer adapted the vocal writing, originally for up to eight parts, for four-part chorus for an Augsburg performance under his direction around 1800.
These discoveries have important consequences for an understanding of the kind of sound Mozart intended, something which is only clear from Mozart’s complete autograph for the Kyrie and Gloria movements. 45 years ago, an edition of the mass was published in the New Mozart Edition, faithfully based on the sources, but one which consciously avoided making a reconstruction such as would be necessary for a performance. In collaboration with the Stiftung Mozarteum Salzburg, a new edition has now been published which takes into consideration the latest state of research and, unlike a scholarly Complete Edition, the practical requirements for performance as well.
In the case of the Sanctus (with “Hosanna”) and Benedictus, Mozart’s score of the vocal parts (double choir) and strings has been lost; here it was important to divide the four-part choral writing, as surviving in Fischer’s arrangement, into two choirs again and to reconstruct the apparently missing choral parts by reference to the instrumental parts, a task which has been achieved by means of a detailed comparison. Of particular importance for the reconstruction was the observation that in the few Salzburg church compositions of the 18th century for double choir (including Mozart’s Offertorium “Venite populi” KV 260), the three trombones always played with the vocal parts of the first choir.
For the first two partial movements of the Credo, Mozart prepared a complete draft score which contains all the vocal parts, the instrumental bass and the most important instrumental parts. It goes without saying that Mozart had intended trumpets and timpani to be used at the beginning of the Credo. Regarding a fitting, stylistically appropriate addition of the string accompaniment to the soprano aria “Et incarnatus est”, it has long been accepted that the aria “Deh vieni non tardar” from “Le nozze di Figaro” offers particularly reliable reference points.
Ulrich Leisinger
(from [t]akte 2/2018 – translation: Elizabeth Robinson)