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The mass is classed as a missa longa due to its length. However, due to its lack of extended writing for the solo parts, it has also been categorised as a missa brevis. The occasion the mass was composed for remains debatable. It may have been composed at the Archbishop Colloredo's request for a special occasion at the Salzburg Cathedral, or at the directive of a different priest – Colloredo's preference for brief settings makes it unlikely that he would have approved of the missa longa. Alternatively, it may have been composed for performance at St Peter's Church.
The mass is divided into six movements.
KyrieAllegro, C major,
GloriaAllegro con spiritu, C major,
"Qui tollis peccata mundi" Andante, G minor, 4
"Quoniam tu solus Sanctus" Allegro con spiritu, C major,
CredoAllegro, C major, 4
"Et incarnatus est" Adagio ma non troppo, C major,
"Et resurrexit" Molto allegro, C major,
"Et in Spiritum Sanctum Dominum" Allegro, G major, 4
Salzburg Cathedral may have been the first performance venue of the mass.
