Mozart died in the early hours of Monday 5th December 1791 of chronic kidney failure and a streptococcal infection. His body was consecrated in the Chapel of the Cross in the north west corner of St Stephen’s Cathedral, and then taken to the cemetery of St Mark’s, about 6 miles outside of the walls of Vienna where, due to his financial circumstances, it was buried in an unmarked communal grave. Süßmayr agreed to complete the work for Konstanza. Payment for the work had already been received, and presumably spent, and she must have worried that if it was handed over incomplete the commissioning patron would refuse to accept it and expect his money to be returned. The work was later given a performance in a benefit concert for Konstanza in 1793, to raise funds for the poverty stricken widow. Here it was sung by a mixed SATB choir of 16 opera singers and the performance was in a café accompanied by fortepiano.

In Mozart’s autograph score the vocal parts are complete where the movement has been set (the Sanctus, Benedictus and Agnus Dei were not attempted) and there are some sketches for the orchestral parts, and some sections of figured bass which indicate his harmonic intentions. He left a number of other fragments, such as the trombone solo at the opening of the Tuba Mirum. The rest of the work and the orchestration is by Süßmayr; presumably based in part on conversations held with Mozart. By the time he started work on the Requiem Mozart was already terminally ill, and parts of the composition were actually written whilst on his death-bed. A copy was made of the completed score before it was handed over to Count Walsegg’s envoy, but no mention was made of Sußmayer’s part in its composition, and for many years it was generally believed that Mozart had indeed written the entire Requiem. Amongst Mozart’s circle, however, it was common knowledge that the composer had not lived to see its completion. Consequently, some considerable controversy later ensued as to the work’s authenticity, compounded by the fact that Count Walsegg’s score disappeared for nearly fifty years, only to be rediscovered in 1839.

Fortunately, this complete score and Mozart’s original unfinished manuscripts did both survive, and are now securely housed in the Vienna State Library. Comparison of the two sources has shown quite clearly which parts Mozart either wrote down or indicated in the form of sketches and footnotes, and which parts were completed and composed by his pupil. However, the matter is not quite that straightforward. Since Mozart is known to have played through and discussed the music with Süßmayr, it seems more than plausible that he would have passed on ideas that he carried in his head but had not yet written down, and for this reason we can never be entirely sure of precisely what is Mozart’s and what is Süßmayr’s. It is well known that Mozart developed a strong interest in the music of J. S. Bach shortly after his arrival in Vienna in 1781, and how deeply this influenced him. Imitative counterpoint became an increasingly important element in his instrumental works, culminating in the great fugal passages of the last symphonies. Given that fugue was traditionally a province of liturgical music, Mozart would have felt even more inclined to exercise his skill as a contrapuntist in composing the Requiem. It is not surprising, then, that the opening phrases of the Introit contain imitative counterpoint, or that the Kyrie is set as a double fugue of great brilliance and power. More contrapuntal writing is heard elsewhere, and frequently, in the work. The mature music of the Requiem is completely different from the youthful exuberant music of the Vespers, composed only some ten years earlier.

Peter Parfitt