In Mozart’s day composers wrote sacred music as it matter of conrse. He too conformed to this practice, generally accepting e.g. in his Masses liturgical requirements or musical traditions. Some of his sacred works, however, far exceed what had become standard expectations; among these is the “Requiem”, combining traditional thoughts handed down from the past with new ones, brought together within the common denominator of his own style and making the motto “Opus summum viri summi” which J. A. Hiller wrote at the head of his own copy, appropriate from many aspects.
On the one hand the influence of Bach and Handel is obvious in the counterpoint and rhetoric; on the other, in his harmonies and colours Mozart looked well forward into the l9th century, thus creating a synthesis of both style and character in which the archaic is joined to the subjectively emotional. The opening of the “Requiem” extends, in its expressiveness, far beyond the liturgical framework into the realms of an essentially personal creed. The predominance of basset horns and bassoons indicates, particularly in the first part, a romantic sonority of subjective resignation which corresponds to Mozart`s own views on death as set out in a letter to his father dated 1787.
Even so, Mozart, who never balked at presenting man’s most pronounced feelings, contrasted the conciliatory attitude at the beginning with individual revolt: the orchestral figures at “Exaudi orationem meam” are of an almost waspish obduracy. The romantic aspects of the work are exemplified by the “Kyrie” fugue with its bold harmonic excursions which characterise the dark, profound aspects. The dramatic manner in which Mozart, in the "Dies irae”, combined the objectively devotional with the subjectively devout is also highly significant.
After the passionate insistence of the “Rex tremendae majestatis” with its almost expressionistic emphasis on thc tremendous, the pinnacle of the work is reached in the humble prayer and deeply moving fearfulness of the “Recordare”. Its completely romantic mood is followed by the realistically descriptive “Confutatis maledictis“, once again full of bold harmonies which must have been quite intimidating in l79l and almost foreshadow Wagner with their chromaticism. Only the first eight bars of the “Lacrimosa” are by Mozart himself. The Sanctus, Benedictus and Agnus Dei may be based on his sketches but bear unmistakeable marks of his 25 year old pupil Franz Xaver Süssmayr, who completed the torso. The quotation of the opening, “Requiem aeternam" in the concluding “Lux aeterna" is said to be in accordance with the composer`s wishes. For all its incompleteness, the work represents a synthesis not only of Mozart's own achievements but also of 18th and 19th century music.
Mozart worked on the “Requiem” from the summer of l791 until his death in early December of thc same year, interrupted twice, by the "Magic Flute” and "La clemenza di Tito". The title page of the “Requiem” autograph bears the date 1792 in his own hand: obviously he planned to complete in the following year the work which had been begun as a result of a commission of which the romantic circumstances have created a whole legend. Count Waldcgg, who had commissioned the work, is said to have had it performed in 1793.