Requiem (Mozart)

The Requiem in D minor is a mass for the dead composed by Wolfgang Amadeus Mozart in Vienna in the second half of 1791, left unfinished at his death on December 5 of that year. Mozart completed only the opening movement, the Introitus, in full; the composer Joseph Eybler began work on the remainder before the task passed to Franz Xaver Sussmayr, who composed additional sections and orchestrated what Mozart had left incomplete. It had been commissioned anonymously by Count Franz von Walsegg to mark the anniversary of his wife's death, apparently intending to pass the work off as his own composition, a plan undone when Mozart's widow Constanze arranged a public benefit performance that made his authorship known; despite long debate over how much of the completed score is genuinely Mozart's, the Sussmayr version remains the one most widely performed.