Settings of the Ordinary of the Mass

For many centuries it had been customary to set the entire Mass to music. The lessons and orations would be recited by the priest, deacon, subdeacon, or other appropriate clerical figure, while everything else would be chanted by the schola or choir, perhaps also allowing for congregational participation. These chants conform to the basic portions of the Mass: the Proper (Introit, Gradual, Alleluia, Offertory, Communion), which changed with each day, depending upon the particular season or feast, and the Ordinary (Kyrie, Gloria, Credo, Sanctus, Agnus Dei, sometimes also the dismissal Ite missa est), which remained constant. (in practice the Ordinary too might change, thanks to tropes for specific occasions.) Though polyphonic settings of the Ordinary appear as early as the Winchester Troper (c. 1050), the first systematic use of liturgical polyphony was not until Leonin's Magnus Liber(c. 1160). Here polyphony provided showpieces in the Proper of the Mass for the soloists on the great feast days. After Perotin, hardly any liturgical polyphony was written until theIvrea Codex and the subsequent Apt manuscript (c. 1385), both from the Avignon circle, where polyphonic settings of sections from the Ordinary begin to assume importance.

Most l4th-century polyphonic settings of the Ordinary are of single movements. Typically scribes grouped these movements by section in the manuscripts, so that five Kyries might be followed by seven Glorias, then six Credos, etc. The choirmaster could then select those movements best suited to the occasion. Once one or more movements of the Ordinary get performed polyphonically, polyphonic settings of the entire Ordinary become inevitable. That just such a practice gradually became accepted is clear from four Ordinary compilations, known today from the present location of their manuscript sources. These are the Masses of Tournai, Toulouse, Barcelona, and the Sorbonne.

But the greatest of the 14th-century polyphonic Mass Ordinaries, and the first to survive in a complete setting by one composer, is that by Guillaume de Machaut (c. 1300-c. 1377). It is Machaut's largest work and the best-known extended composition of the entire 14th century. While the anonymous settings are largely in three parts, Machaut employs four voice parts throughout. The Kyrie, Sanctus, Agnus Dei, and Ite missa est are all built upon chant tenors and are wholly or partially isorhythmic. The Gloria and Credo are given essentially syllabic, note-against-note settings; such a practice becomes increasingly customary, owing to the sheer length of the texts. What is unique about Machaut's setting of these two movements is the free strophic patterns into which they are organized. In fact, at one time Machaut's Mass was thought to be cyclic in the Renaissance sense that the movements were melodically related; this theory is now largely discredited. Nonetheless, its consistency of style, complexity, and thoroughgoing rhythmic organization suggest that it is a late work and one intended to be performed whole.

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