Missa in D "Missa brevis"

The celebration of Mass is the central element of the Roman Catholic Liturgy. Musical settings of the Ordinary of the Mass consist of Kyrie, Gloria, Credo, Sanctus (with Osanna), Benedictus (and Osanna), and Agnus Dei. In Salzburg, a highly differentiated system developed over time to determine which celebrations required which type of composition. Some of the earliest masses by Wolfgang Amadé Mozart were composed for special occasions such as the consecration of priests or churches. After his appointment as concertmaster, he began composing music for Salzburg Cathedral on a regular basis and, in the 1770s, he was the most prolific composer of church music in the city. The use of trumpets and timpani indicates that most of these settings were intended for feast days when the Mass was held by the Prince-Archbishop himself. Masses in Southern Germany and Austria do not ordinarily include viola parts. After his move to Vienna, Mozart never held a church position again. Nonetheless, he began to write a number of masses there, although they remain as fragments. In April 1791, Mozart’s application to serve as substitute for Leopold Hofmann, the ailing capellmeister at St. Stephen’s Cathedral in Vienna, was granted, but he did not live to assume this position. The Requiem, a mass for the dead offered for the repose of the soul, uses a particular form of the Roman Missal. In Salzburg and Vienna, musical settings of the Requiem were written only for special occasions.