The one thing to always bear in mind when you listen to the Mozart Requiem is that he didn’t write all of it. He wrote the first movement but his unfinished manuscripts had to be used to actually finish the work.

Wolfgang Amadeus Mozart was commissioned by a secretive person (we now know it was a rather eccentric Count von Walsegg-Stuppach, and through intermediaries) to write a Requiem and was given half his commission in advance. He set about this task in mid-1791 when he still had quite good health.

Mozart was a great composer of repute by this time, at the age of only 35, and had completed a vast list of compositions, from piano concertos to string-quartets, sonatas to operas, symphonies to solo works. Perhaps his Mass in C minor, written in 1783 and an immediate success was the reason the Count wanted Mozart’s music for himself?

However there is possibly another explanation. The Count was a very rich aristocrat who was also an amateur musician. He had a habit of commissioning works from composers of the day and passing them off as his own. His young wife of 20 years old died in February 1791 and he sent an anonymous messenger to Mozart soon afterwards requesting him to compose a requiem mass.

Walsegg-Stuppach intended to have the mass performed as his own, once completed, he being only 28 at the time, never to remarry.

Mozart died before he could complete this epic work, although he left quite a few manuscript pages showing what he was thinking of, some in quite a bit of detail, enabling the work to be completed by others.

Constanze Mozart, after Mozart’s death, was keen to get the work finished because of the 50% still owing upon completion. She asked Joseph von Eybler, a friend and pupil of Mozart to finish the score. He did some work on it but, because of his own composing, felt he was unable to complete the work and returned it.

Franz  Xaver Sussmayer, another friend and pupil of Mozart’s was then given the task of finishing the work.

Using Mozart’s original drafts, Eybler’s additional work, both his own competency and the fact that he had been taught by Mozart, he finished the requiem. He had to add the movements which would be normal in a requiem, whilst ending with adaptations of the first two movements.

It has been thought that other composers may have helped either orchestrate or assist Sussmayer in this task but we will probably never know, and this was denied at the time. When finished by Sussmayer in 1792 the score was quickly sent to Count Walsegg with the counterfeit signatures and initials of the dead Mozart.

Wonderfully controversial, particularly if one looks into what was occurring at the time, the music actually speaks for itself. Mozart stands out as being spectacular whilst the other ‘helpers’ to complete the requiem show less of the Great composer than the pupil or pupils who are trying hard to live up to the Master’s expectations.

The Mozart requiem is a fabulous work which becomes even more interesting when you know a bit about it. Have a listen and see if you can spot the difference.