Mozart's Requiem

Requiem
by Wolfgang Amadeus Mozart
The first page of Mozart's autograph
Key	D minor
Catalogue	K. 626
Text	Requiem
Language	Latin
Composed	1791 (1791)
Scoring	four soloists chorus orchestra

The Requiem in D minor, K. 626, is a Requiem Mass by Wolfgang Amadeus Mozart. He composed it in Vienna in 1791, and it was left unfinished at the composer's death on 5 December the same year. A completion dated 1792 by Franz Xaver Süssmayr was delivered to Count Franz von Walsegg, who had anonymously commissioned the piece for a Requiem service to commemorate the anniversary of his wife's death on 14 February.

The autograph manuscript (acquired by the Austrian National Library in 1831–38) shows the finished and orchestrated Introit in Mozart's hand, as well as detailed drafts of the Kyrie and the sequence Dies Irae as far as the first eight bars of the "Lacrymosa" movement, and the Offertory. It cannot be shown to what extent Süssmayr may have depended on now lost "scraps of paper" for the remainder; he later claimed the Sanctus and Agnus Dei as his own. Walsegg probably intended to pass the Requiem off as his own composition, as he is known to have done with other works. This plan was frustrated by a public benefit performance for Mozart's widow Constanze. She was responsible for a number of stories surrounding the composition of the work, including the claims that Mozart received the commission from a mysterious messenger who did not reveal the commissioner's identity, and that Mozart came to believe that he was writing the requiem for his own funeral.

The Requiem is scored for 2 basset horns in F, 2 bassoons, 2 trumpets in D, 3 trombones (alto, tenor & bass), timpani (2 drums), violins, viola and basso continuo (cello, double bass, and organ). The vocal forces include soprano, contralto, tenor, and bass soloists and an SATB mixed choir.