Welcome to Mozart's Requiem Mass (Introit and Kyrie)
Welcome to your complete revision guide for one of the most famous and dramatic pieces in the choral repertoire: Wolfgang Amadeus Mozart’s Requiem Mass in D minor, K. 626. For your CCEA A2 3 exam under the Sacred Vocal Music (Mass/Requiem Mass) Area of Study, you are required to study the first two connected movements: the Introit (Requiem aeternam) and the Kyrie eleison.
Don't worry if counterpoint and classical score analysis feel daunting at first. We will break down Mozart's historical context, his deliberate choice of dark orchestral colours, and the exact bar-by-bar musical features you need to master for your exam.
---1. Historical Background & The Commission
The Story Behind the Score
• Composer: Wolfgang Amadeus Mozart (1756–1791).
• Date of Composition: 1791 (Mozart's final, uncompleted masterpiece before his death on 5 December 1791).
• Catalogue Designation: K. 626 (from the Köchel catalogue of Mozart's works).
• The Secret Commission: The work was commissioned anonymously by an eccentric nobleman, Count Franz von Walsegg, via a mysterious messenger. Count Walsegg wanted a Requiem Mass to commemorate his late wife, Countess Anna von Walsegg (who died in February 1791), and intended to pass the composition off as his own!
• Who Finished It? The Introit (Requiem aeternam) is the only movement Mozart completed and fully orchestrated in his own hand. The Kyrie was left fully drafted with choral voices, basso continuo, and key orchestral motifs. Following Mozart’s death, his pupil and collaborator Franz Xaver Süssmayr completed the instrumentation and integrated the score.
Did You Know? A Requiem is a Mass offered for the repose of the souls of the deceased. The word comes from the opening Latin text: "Requiem aeternam dona eis, Domine" ("Grant them eternal rest, O Lord").
---2. Instrumentation & Orchestral Colour
Mozart chose a uniquely dark, sombre, and archaic orchestral palette to reflect grief, mortality, and solemn prayer. Examiners frequently test your knowledge of this specific instrumentation.
Woodwind
• 2 Basset horns in F (an alto clarinet with a rich, dark, mournful lower register).
• 2 Bassoons.
• Crucial Point to Remember: Standard bright woodwinds—flutes, oboes, and standard clarinets are completely omitted.
Brass & Percussion
• 2 Trumpets in D.
• 3 Trombones (Alto, Tenor, Bass) — these play colla parte (literally "with the part"), meaning they double the Alto, Tenor, and Bass vocal lines of the choir to reinforce the liturgical polyphony.
• Timpani tuned in D and A (tonic and dominant).
Strings & Continuo
• Violins I & II, Violas, Violoncellos, and Double Basses.
• Basso Continuo with Organ.
Vocal Forces
• SATB Chorus (Soprano, Alto, Tenor, Bass).
• Solo Soprano (features exclusively in the Te decet hymnus section of the Introit).
Key Takeaway: The low-pitched woodwind combination (basset horns + bassoons) combined with trombones doubling the choir creates an austere, solemn sound-world tailor-made for a funeral liturgy.
---3. Detailed Analysis: Movement 1 – Introit (Requiem aeternam)
• Key: D minor (a key Mozart frequently associated with tragedy, death, and the supernatural).
• Metre: 4/4.
• Tempo: Adagio.
• Structure: Continuous, through-composed liturgical form divided into distinct textual and musical sections.
Section 1: Orchestral Introduction (Bars 1–7)
• The movement opens with a quiet, pulsing tonic pedal point in D played by the bass strings and organ continuo.
• Canonic / Imitative entries: The bassoons enter first with a mournful, rising and falling subject featuring dotted rhythms and sighing figures. The basset horns enter imitatively one bar later.
• The syncopated string figures create continuous, solemn rhythmic momentum.
Section 2: Choral Entry – "Requiem aeternam" (Bars 8–19)
• Vocal Polyphony: The choral Basses enter first on the principal theme (bar 8), followed by imitative entries in ascending order: Tenors (bar 9), Altos (bar 10), and Sopranos (bar 11).
• The violins continue their agitated, syncopated accompaniment underneath.
• Word Painting & Key Shift: For the text "et lux perpetua luceat eis" ("and let perpetual light shine upon them", bar 15), Mozart modulates to F major (the relative major). The choral texture shifts dramatically from dense polyphony to a bright, uplifting homophonic texture to represent "light".
Section 3: "Te decet hymnus" & "Exaudi" (Bars 21–33)
• Solo Soprano Entry: The Soprano soloist sings an ancient liturgical plainsong melody known as the Tonus Peregrinus (a traditional Gregorian psalm tone), functioning here as a cantus firmus.
• Choral Interjections: The lower choral voices (ATB) enter polyphonically beneath the soloist with urgent, pleading cries on "Exaudi orationem meam, ad te omnis caro veniet" ("Hear my prayer; unto thee shall all flesh come").
Section 4: Reprise & Transition (Bars 34–48)
• The opening "Requiem aeternam" text and thematic material return, pulling the music firmly back into D minor.
• The choral counterpoint becomes increasingly intense, featuring dissonant suspensions, heavy chromaticism, and expressive diminished 7th harmonies.
• The Introit ends on a dominant chord and moves directly attacca (without a break) straight into the Kyrie.
4. Detailed Analysis: Movement 2 – Kyrie eleison
• Key: D minor.
• Metre: 4/4.
• Tempo: Allegro.
• Form: Double Fugue (a fugue based on two distinct, contrasting subjects that are stated and developed simultaneously).
The Two Contrasting Subjects
Think of a double fugue as two characters speaking at once with completely different personalities:
• Subject 1 (Kyrie eleison - "Lord have mercy"):
Stated in heavy, angular, disjunct notes. It features a severe, archaic Baroque profile characterized by a dramatic descending diminished 7th interval. This theme is heavily indebted to the Baroque tradition (reminiscent of choruses by J.S. Bach and G.F. Handel, such as "And With His Stripes" from Messiah).
• Subject 2 / Countersubject (Christe eleison - "Christ have mercy"):
Stated simultaneously with Subject 1. In complete contrast, it is fast, conjunct, and highly melismatic with flowing, rapid semiquaver runs.
Fugal Exposition & Texture
• Simultaneous Opening (Bar 1): The choral Basses sing Subject 1 (Kyrie), while the Tenors enter at the exact same moment singing Subject 2 (Christe).
• Answer Entries: The Altos and Sopranos enter next as a paired entry, singing the answers in the dominant key (A minor).
• Orchestral Role: The strings double the vocal lines with motoric, driving energy or provide rapid independent counter-melodies, while the three trombones play colla parte to support the choir.
Development and Climactic Ending
• Mozart develops both subjects through intricate counterpoint, cycling through closely related keys (including F major, G minor, A minor, and B flat major).
• Uses intense contrapuntal devices including stretto (overlapping entries where voices enter before the previous voice finishes) and resonant dominant pedals.
• The Final Cadence: The fast semiquavers come to a dramatic halt on an Adagio pause bar featuring an unresolved dominant/diminished chord with a suspended note.
• The movement resolves onto a grand, archaic bare 5th cadence (containing only the notes D and A with no third). Leaving out the F/F# gives the ending an ancient, hollow, and eternal medieval sound.
Memory Trick:
• Kyrie = Knotted, angular, diminished 7th steps.
• Christe = Continuous running semiquaver melismas.
5. Common Pitfalls to Avoid in the Exam
• Wrong Movements: Other UK exam boards prescribe movements like the Dies Irae or Lacrimosa. For CCEA A2 3, focus strictly on the Introit and Kyrie.
• Standard Woodwinds: Never say Mozart uses flutes, oboes, or standard clarinets! He specifically scores for 2 Basset horns and 2 Bassoons.
• Fugue Classification: Do not describe the Kyrie as a "simple fugue". It is a Double Fugue with two subjects introduced simultaneously.
• Number of Soloists: The Introit does not use a solo vocal quartet. The only solo voice in these two movements is the Solo Soprano in the Te decet hymnus.
• Plainsong Reference: Remember to name the Tonus Peregrinus when discussing the Soprano solo in the Introit.
6. Quick Revision Checklist
• Can you describe the role of Count Walsegg and Franz Xaver Süssmayr?
• Can you list all instruments in Mozart's sombre orchestra?
• Do you know what colla parte means for the trombones?
• How does Mozart depict "light" (et lux perpetua) in bar 15 of the Introit?
• What is the Tonus Peregrinus and who sings it?
• Can you describe the musical differences between Subject 1 (Kyrie) and Subject 2 (Christe)?
• How does the Kyrie movement conclude (the final chord)?