The Requiem in D minor, K. 626, is a Requiem Mass written by Wolfgang Amadeus Mozart (1756–1791). Mozart began writing part of the Requiem in Vienna in late 1791, but he did not finish it before he died on December 5, 1791. A completed version of the Requiem was later given to Count Franz von Walsegg, who had asked Mozart to write it for a Requiem service on February 14, 1792, to honor the first anniversary of the death of his wife, Anna, who had died at age 20 on February 14, 1791.

The original manuscript shows that Mozart completed and added musical details to the Introit. It also includes detailed drafts of the Kyrie, the Sequence (which includes the first eight bars of the Lacrimosa), and the Offertorium. Joseph Eybler and later Franz Xaver Süssmayr finished the remaining parts, added other movements, and made a clean copy of the completed sections for Walsegg. They tried to copy Mozart’s handwriting but mistakenly labeled the copy “1792.” It is unclear how much Süssmayr relied on lost notes for the rest of the work. He later claimed to have written the Sanctus, Benedictus, and Agnus Dei himself.

Walsegg likely planned to claim the Requiem as his own work, as he had done with other compositions. This plan was stopped by a public performance held to help Mozart’s widow, Constanze. Constanze shared stories about the Requiem, including claims that Mozart received a secret commission from an unknown messenger and that he believed he was writing the Requiem for his own funeral.

Besides the version completed by Süssmayr, many other versions of the Requiem have been created by composers and music experts in the 20th and 21st centuries. At least 19 different versions have been made, with 11 of them created after 2005.

Instrumentation

The Requiem uses the following instruments: two basset horns in the key of F, two bassoons, two trumpets in the key of D, three trombones (alto, tenor, and bass), two timpani (drums), violins, viola, and basso continuo (cello, double bass, and organ). The parts for the basset horns are sometimes played on standard B♭ or A clarinets, or on alto clarinets, even though this changes the sound.

The vocal parts include a soprano, contralto, tenor, and bass soloist, along with a mixed choir with soprano, alto, tenor, and bass voices.

Structure

Süssmayr's completion of the Requiem divides it into eight sections. The sections starting with the Sanctus are not found in Mozart's original manuscript. Mozart may have wanted to include the Amen fugue at the end of the Sequentia, but Süssmayr did not add it in his completion. The table below shows the eight sections in Süssmayr's completion, including their details: the title, vocal parts (solo soprano (S), alto (A), tenor (T), and bass (B)) [in bold] and four-part choir SATB, tempo, key, and meter.

Music

The Requiem begins with a seven-measure instrumental introduction. The woodwinds (first the bassoons, then the basset horns) present the main theme of the piece using imitative counterpoint, where musical lines copy each other. The first five measures of this passage (without the accompaniment) are shown below.

This theme is based on Handel’s opening chorus “The ways of Zion do mourn” from his 1737 Funeral Anthem for Queen Caroline, HWV 264. Many parts of the work reference this passage, especially in the coloratura of the Kyrie fugue and in the ending of the Lacrymosa.

The trombones then signal the choir’s entrance. The choir begins the theme, with only the basses singing for the first measure, followed by other voices joining in. The chords in the accompaniment use syncopated and staggered rhythms, creating a solemn and steady sound. A soprano solo sings the text “Te decet hymnus” in the tonus peregrinus. The choir continues, repeating the psalmtone while singing the “Exaudi orationem meam” section. Then, the choir and orchestra perform the principal theme using downward-gliding sixteenth notes. The melodies, whether held or moving downward, change and interweave, with sections in counterpoint and unison (e.g., “Et lux perpetua”) alternating. These elements create the charm of this movement, which ends with a half cadence on the dominant.

The Kyrie follows immediately (attacca). It is a double fugue based on a cruciform melody (a cross shape formed by connecting two of the theme’s four notes), a technique used by composers like Bach, Handel, and Haydn. The counter-subject comes from the final chorus of Handel’s Dettingen Anthem, HWV 265. The first three measures of the basses (theme) and altos (counter-subject) are shown below.

The contrapuntal motifs of this fugue include variations on the two themes from the Introit. At first, upward diatonic sixteenth-note patterns are replaced by chromatic patterns, increasing the intensity. This section is challenging for the upper voices, especially the soprano. A final section in a slower (Adagio) tempo ends on an “empty” fifth, a construction that became outdated during the classical period, giving the piece an ancient feel.

The sequence “Dies irae” (“Day of Wrath”) is a strophic hymn divided into six sections by Mozart. The first verse begins with powerful orchestral and choral elements, including tremolo strings, syncopated figures, and repeated brass chords. A rising chromatic run of sixteenth notes leads into a chromatic harmonic progression as the chorus sings “Quantus tremor est futurus” (“what trembling there will be” in reference to the Last Judgment). This material is repeated with harmonic development before the texture shifts to a trembling unison figure, with tremolo strings evoking the “Quantus tremor” text.

Mozart’s inspiration is evident in the “Tuba mirum” (“Hark, the trumpet”) movement. It begins with a sequence of three notes in an arpeggio, played in B♭ major by a solo tenor trombone, unaccompanied, following the German translation of the Latin word “tuba” (posaune). Two measures later, the bass soloist enters, imitating the same theme. At measure 7, a fermata occurs—the only solo cadenza in the entire work. The final quarter notes of the bass soloist signal the tenor’s entrance, followed by the alto and soprano in a dramatic fashion.

On the text “Cum vix justus sit securus” (“When only barely may the just one be secure”), the quartet sings in a homophonic style, all voices singing together without accompaniment. They emphasize the words “cum” and “vix” on the “strong” (1st and 3rd) and “weak” (2nd and 4th) beats. The violins and continuo respond each time. This “interruption” (interpreted as the moment before the Last Judgment) is heard softly, then loudly, and finally quietly, building into a crescendo that ends with a perfect cadence.

A descending melody made of dotted notes is played by the orchestra to introduce “Rex tremendae majestatis” (“King of tremendous majesty,” referring to God). The choir cries out “Rex” during the orchestra’s pauses. Surprisingly, the choir’s “Rex” syllables fall on the “weak” beat of the measure. The choir then adopts the dotted rhythm of the orchestra, forming a style Wolff describes as a form of “paying homage to princes,” or more simply, a standard way of saluting royalty or divinity. This movement, though only 22 measures long, includes many variations: homophonic singing and contrapuntal choral passages alternate frequently, ending with a nearly unaccompanied choral cadence on an open D chord (as seen earlier in the Kyrie).

The “Recordare” (“Remember merciful Jesus”) is a prayer not to be forgotten on the last day. At 130 measures, it is the longest movement and the first in triple meter (4). It sets seven stanzas of the “Dies irae.” Its structure resembles sonata form, with an exposition (mm. 1–37), a development (mm. 38–92), and a recapitulation (mm. 93–98).

In the first 13 measures, the basset horns introduce the first theme, inspired by Wilhelm Friedemann Bach’s Sinfonia in D minor. This theme is enriched by a counterpoint from the cellos, which play descending scales repeated throughout the movement. The counterpoint of the first theme extends the orchestral introduction with chords, recalling the beginning of the work and its rhythmic and melodic shifts (e.g., the first basset horn starts a measure after the second but a tone higher; the first violins align with the second violins but a quarter note later). The introduction is followed by the vocal soloists, who sing the first theme: the alto and bass (from m. 14), then the soprano and tenor (from m. 20). Each time, the theme ends with a hemiola (mm. 18–19 and 24–25). The second theme arrives on “Ne me perdas,” with an accompaniment that contrasts with the first theme’s descending scales, using only repeated chords. The exposition concludes with four orchestral measures based on the counter-melody of the first theme (mm. 34–37).

The development of the two themes begins at m. 38 on “Quaerens me.”

Liturgical texts

Eternal rest give unto them, O Lord, and let perpetual light shine upon them. A hymn, O God, becometh Thee in Zion; and a vow shall be paid to Thee in Jerusalem. Hear my prayer; all flesh shall come to Thee. Eternal rest give unto them, O Lord, and let perpetual light shine upon them.

Lord, have mercy on us. Christ, have mercy on us. Lord, have mercy on us.

Day of wrath, day of anger will dissolve the world in ashes, as foretold by David and the Sibyl. Great trembling there will be when the Judge descends from heaven to examine all things closely! The trumpet will send its wondrous sound throughout earth's sepulchres and gather all before the throne. Death and nature will be astounded, when all creation rises again, to answer the judgment. A book will be brought forth, in which all will be written, by which the world will be judged. When the judge takes his place, what is hidden will be revealed, nothing will remain unavenged. What shall a wretch like me say? Who shall intercede for me, when the just ones need mercy? King of tremendous majesty, who freely saves those worthy ones, save me, source of mercy. Remember, kind Jesus, my salvation caused your suffering; do not forsake me on that day. Faint and weary you have sought me, redeemed me, suffering on the cross; may such great effort not be in vain. Righteous judge of vengeance, grant me the gift of absolution before the day of retribution. I moan as one who is guilty: owning my shame with a red face; suppliant before you, Lord. You, who absolved Mary, and listened to the thief, give me hope also. My prayers are unworthy, but, good Lord, have mercy, and rescue me from eternal fire. Provide me a place among the sheep, and separate me from the goats, guiding me to Your right hand. When the accused are confounded, and doomed to flames of woe, call me among the blessed. I kneel with submissive heart, my contrition is like ashes, help me in my final condition. That day of tears and mourning, when from the ashes shall arise, all humanity to be judged. Spare us by your mercy, Lord, gentle Lord Jesus, grant them eternal rest. Amen.

Lord Jesus Christ, King of glory, liberate the souls of the faithful departed from the pains of hell and from the bottomless pit. Deliver them from the lion's mouth, lest hell swallow them up, lest they fall into darkness. Let the standard-bearer, holy Michael, bring them into holy light. Which was promised to Abraham and his descendants. Sacrifices and prayers of praise, Lord, we offer to You. Receive them in behalf of those souls we commemorate today. And let them, Lord, pass from death to life, which was promised to Abraham and his descendants.

Holy, holy, holy, Lord God of Hosts. Heaven and earth are full of Thy glory. Hosanna in the highest.

Blessed is He who cometh in the name of the Lord. Hosanna in the highest.

Lamb of God, who takes away the sins of the world, grant them rest. Lamb of God, who takes away the sins of the world, grant them everlasting rest.

Let eternal light shine on them, Lord, as with Your saints in eternity, because You are merciful. Grant them eternal rest, Lord, and let perpetual light shine on them, as with Your saints in eternity, because You are merciful.

History

At the time of Mozart's death on December 5, 1791, only the first movement, Introitus (Requiem aeternam), was fully completed in all the orchestral and vocal parts. The Kyrie, Sequence, and Offertorium were partially completed, with the exception of the Lacrymosa, which ended after the first eight bars. The vocal parts and accompaniment were fully written. Occasionally, some of the main orchestral parts were briefly noted, such as the first violin part in the Rex tremendae and Confutatis, the musical transitions in the Recordare, and the trombone solos in the Tuba Mirum.

What remained to be completed for these sections were mostly accompaniment figures, inner harmonies, and additional orchestral parts to support the vocal lines.

The eccentric Count Franz von Walsegg commissioned the Requiem from Mozart anonymously through intermediaries. The count, an amateur musician who often commissioned works from composers and claimed them as his own, wanted a Requiem Mass to memorialize his wife’s recent death. Mozart received only half of the payment upfront. After his death, his wife, Constanze, wanted to complete the work secretly, submit it as Mozart’s, and collect the final payment. Joseph von Eybler was one of the first composers asked to finish the score. He worked on the movements from the Kyrie up to the Lacrymosa, adding his notes to the incomplete manuscript. He then stopped and returned the manuscript to Constanze.

The task was then given to another composer, Franz Xaver Süssmayr. Süssmayr added orchestration to the Kyrie and later movements, completed the Lacrymosa, and added new sections typical of a Requiem: Sanctus, Benedictus, and Agnus Dei. He also created a final section, Lux aeterna, by adapting the opening movements of the Requiem to fit the words that end the Requiem Mass. Both Süssmayr and Constanze claimed this was done according to Mozart’s instructions.

Other composers may have helped Süssmayr. The Agnus Dei is suspected by some scholars to have been based on Mozart’s instructions or sketches because of its similarity to a section from the Gloria of a previous Mass (Sparrow Mass, K. 220), as noted by Richard Maunder. Others have pointed out that the choral bass in the Agnus Dei quotes the main theme from the Introitus. However, many debates about the work’s authorship focus on the belief that high-quality sections must be Mozart’s, while sections with errors are likely Süssmayr’s.

Another controversy involves a letter from Constanze, which suggested that Mozart left explicit instructions for completing the Requiem on “a few scraps of paper with music on them… found on Mozart’s desk after his death.” Whether Süssmayr was influenced by these scraps, if they existed, remains a topic of debate among musicologists.

The completed score, started by Mozart but largely finished by Eybler and Süssmayr, was sent to Count Walsegg with a forged signature of Mozart and dated 1792. In the 19th century, the various manuscripts were discovered, but many involved left unclear statements about their roles. Despite debates over how much of the music is truly Mozart’s, the version completed by Süssmayr is widely accepted by the public. This acceptance is strong, even though other completions offer logical solutions.

Confusion about the Requiem’s creation was largely caused by Constanze. She had to keep secret that the Requiem was unfinished at Mozart’s death so she could collect the final payment. She also needed to hide Süssmayr’s involvement so Count Walsegg would believe Mozart wrote the entire piece. After receiving the commission, she promoted the work as Mozart’s to continue earning money from its publication and performances. During this time, it was important for the public to believe Mozart wrote the whole piece to increase its value.

Constanze’s actions led to many half-truths and myths about Mozart’s death. According to Constanze, Mozart said he was composing the Requiem for himself and that he had been poisoned. He complained about swelling and fever but continued working on the Requiem until his final day, explaining to his assistant how he planned to finish it.

The myths surrounding the Requiem’s completion include the idea that Mozart’s colleague Antonio Salieri commissioned and finished the Requiem, implicating him in Mozart’s death. This myth appears in Peter Shaffer’s 1979 play Amadeus and the movie based on it. The myth originated from an 1830 play by Alexander Pushkin, Mozart and Salieri, which later became an opera by Rimsky-Korsakov.

Sources written shortly after Mozart’s death contain conflicting details, making it difficult to assemble clear facts about the Requiem’s creation. For example, three sources from within two decades of Mozart’s death cite Constanze as their main source of information.

In 1798, Friedrich Rochlitz, a German biographer and composer, published Mozart anecdotes he claimed to have collected during a meeting with Constanze in 1796. Rochlitz’s account includes these details:

• Mozart did not know who commissioned the Requiem when he accepted the project.
• He had no deadline to complete the work.
• He estimated it would take about four weeks to finish.
• He requested and received 100 ducats when the commission was first offered.
• He started the project immediately after receiving the commission.
• His health was poor from the beginning; he fainted multiple times while working.
• He took a break from writing to visit the Prater with his wife.
• He told his wife he was writing the piece for his own funeral.
• He mentioned “very strange thoughts” about the unexpected commission.
• He noted that Leopold II’s departure for a coronation in Prague was approaching.

The most disputed claim is the timeline. Rochlitz said the messenger arrived long before Leopold II’s departure, but records show Leopold II left in mid-July 1791. Constanze was in Baden from June to mid-July and would not have been present for the commission or the visit to the Prater. Additionally, The Magic Flute (except for its overture and priest’s march) and La clemenza di Tito were completed by mid-July, leaving no time for Mozart to work on the Requiem as described.

Influences

In 1789, Mozart was asked by Baron Gottfried van Swieten to rearrange Handel's Messiah (HWV 56). This work may have influenced Mozart's Requiem. The Kyrie section of the Requiem uses a melody from the "And with His stripes we are healed" chorus in Handel's Messiah, as both share the same four-note musical theme, with only small changes like added musical decorations. This same theme also appears in the finale of Haydn's String Quartet in F minor (Op. 20 No. 5) and in the first measure of the A minor fugue from Bach's Well-Tempered Clavier Book 2 (BWV 889b). Some believe Mozart adapted parts of Bach's fugues for string ensembles (K. 404a Nos. 1–3 and K. 405 Nos. 1–5), though it is not certain if he wrote these arrangements.

Some scholars think the Introitus section of the Requiem was inspired by Handel's Funeral Anthem for Queen Caroline (HWV 264). Another influence may have been Michael Haydn's Requiem in C minor. Mozart and his father played viola and violin, respectively, during the first three performances of this Requiem in 1772. The Introitus of Mozart's Requiem sounds similar to Michael Haydn's Introitus, and the theme in Mozart's "Quam olim Abrahae" fugue directly copies a melody from Haydn's Offertorium and Versus sections in his Requiem. In the Introitus, the soprano sings "Te decet hymnus Deus in Zion," which is taken from the Lutheran hymn "Meine Seele erhebt den Herren." This melody also appears in Bach's cantata Meine Seel erhebt den Herren (BWV 10) and in Michael Haydn's Requiem.

Felicia Hemans's poem "Mozart's Requiem" was first published in The New Monthly Magazine in 1828.

Modern completions

Since the 1970s, some composers and music experts have not been satisfied with the traditional "Süssmayr" completion of the Requiem. They have worked on different ways to finish the Requiem.

The "Amen" fugue

In the 1960s, a sketch for an Amen fugue was found. Some musicologists, Levin and Maunder, think this sketch belongs to the Requiem, specifically at the end of the sequence after the Lacrymosa. However, H. C. Robbins Landon believes the Amen fugue was not meant for the Requiem. Instead, he suggests it may have been part of a different, unfinished mass in D minor, which also included the Kyrie K. 341.

Strong evidence supports the idea that the Amen fugue is part of the Requiem. First, the main theme of the fugue matches the principal subject of the Requiem, which appears at the beginning and throughout the work in an exact reverse. Second, the sketch for the Amen fugue was found on the same page as a sketch for the Rex tremendae, along with a sketch for the overture of Mozart’s last opera, The Magic Flute. This places the sketch’s creation in late 1791. During this time, the word “Amen” only appears in the Requiem’s sequence. Third, Levin notes in his book that adding the Amen fugue at the end of the sequence completes a design where each major section of the Requiem ends with a fugue.

Autograph at the 1958 World's Fair

The autograph of the Requiem was shown at the World's Fair in Brussels in 1958. During the fair, someone managed to access the manuscript and tore off the bottom right-hand corner of the second-to-last page (folio 99r/45r). This part of the page contained the words "Quam olim d: C:" (an instruction that the "Quam olim" fugue in the Domine Jesu section should be repeated from the beginning at the end of the Hostias). The person responsible has not been identified, and the torn fragment has not been found.

If the most widely accepted theory about who wrote the Requiem is correct, then "Quam olim d: C:" were the last words Mozart wrote before he died.

Arrangements

The Requiem and its parts have been arranged for different instruments many times. Keyboard arrangements, especially for the Confutatis and Lacrymosa movements, show how composers adapted the music to balance keeping the Requiem's character and making it playable. Karl Klindworth's piano solo (around 1900), Muzio Clementi's organ solo, and Renaud de Vilbac's harmonium solo (around 1875) used creative methods to achieve this. In contrast, Carl Czerny wrote a piano version for two players, which allowed him to keep the full score but changed how the music sounded. Franz Liszt's piano solo (around 1865) changed the Requiem's character the most, using musical techniques that highlight the piano's abilities.