Requiem (Mozart)

Lore & Background

The autograph manuscript shows the finished and orchestrated movement of the Introit in Mozart's hand, and detailed drafts of the Kyrie, the Sequence (including the first eight bars of the Lacrimosa), and the Offertorium.

Reader's Guide

The Requiem is scored for two basset horns in F, two bassoons, two trumpets in D, three trombones (alto, tenor, and bass), timpani, violins, viola, and basso continuo. The vocal forces consist of soprano, contralto, tenor, and bass soloists and an SATB mixed choir. Süssmayr's completion divides the Requiem into eight sections: Introitus, Kyrie, Sequentia (Dies irae, Tuba mirum, Rex tremendae, Recordare, Confutatis, Lacrimosa), Offertorium, Sanctus, Benedictus, Agnus Dei, and Communio. All sections from the Sanctus onwards are not present in Mozart's manuscript fragment.

Did You Know?

• Walsegg probably intended to pass the Requiem off as his own composition, as he is known to have done with other works.
• Constanze Mozart was responsible for stories including that Mozart received the commission from a mysterious messenger and came to believe he was writing the Requiem for his own funeral.
• The Kyrie is a double fugue on a cruciform melody, with the counter-subject derived from a fugue subject by Handel, specifically from his 'Dettingen Te Deum' or a similar Handel fugue, not from 'The Messiah'.
• The Tuba mirum movement begins with a solo trombone introducing the theme alone, after which the bass voice enters—the trombone does not accompany the voice throughout the movement.

The Commission and Walsegg's Ambition

She had passed at just twenty years old on the same date the previous year. What makes the commission particularly intriguing is Walsegg's known habit of presenting other composers' works as his own, and he almost certainly intended to do the same here. His scheme was derailed, however, by a public benefit performance staged for Mozart's widow Constanze. She became the keeper of several dramatic narratives surrounding the work's creation, including the tale of a mysterious anonymous messenger delivering the commission and the belief that Mozart came to think he was composing his own funeral music. These stories, whether fact or embellishment, have colored how the Requiem is understood to this day.

The Unfinished Score and the Question of Authorship

The autograph manuscript preserves a clear boundary between what Mozart completed and what remained open. In his own hand, we find the fully orchestrated Introit, detailed drafts of the Kyrie, the Sequence (extending through the first eight bars of the Lacrimosa), and the Offertorium. Everything beyond that point was filled in by Joseph Eybler and then Franz Xaver Süssmayr, who also composed additional movements and produced a clean copy for delivery to Walsegg. Süssmayr later claimed the Sanctus, Benedictus, and Agnus Dei as his own compositions, a claim that has fueled centuries of debate over where Mozart's genius ends and another composer's hand begins.

Musical Architecture and the Handel Connection

The Requiem's scoring is distinctive: two basset horns in F, two bassoons, two trumpets in D, three trombones (alto, tenor, bass), timpani, strings, and basso continuo with organ. The vocal forces include four soloists and a full SATB choir. This Handel influence echoes throughout, appearing in the Kyrie fugue's coloratura and the Lacrimosa's conclusion. The Kyrie itself is a double fugue built on a cruciform melody, a device shared by Bach, Handel, and Haydn, with its counter-subject drawn from Handel's Dettingen Anthem. The Dies irae erupts with tremolo strings and syncopated brass, while the Tuba mirum features a solo tenor trombone arpeggio and the work's only solo cadenza.

The Ongoing Quest for Completion

This sustained effort reflects the persistent uncertainty about Mozart's intentions: he may have planned an Amen fugue to close the Sequence, a feature Süssmayr omitted. The basset horn parts, originally written for F basset horns, are now commonly performed on B-flat or A clarinets or the related alto clarinet, a substitution that inevitably alters the work's timbral character. Each new completion represents a different interpretation of what the surviving fragments imply, keeping the Requiem in a state of perpetual musical conversation between the eighteenth century and the present.