Messe de Nostre Dame

Messe de Nostre Dame (Mass of Our Lady) is a polyphonic mass composed before 1365 by French poet and composer Guillaume de Machaut (c. 1300–1377). Widely regarded as one of the masterpieces of medieval music and of all religious music, it is historically notable as the earliest complete setting of the Ordinary of the Mass attributable to a single composer (in contrast to earlier compilations such as the Tournai Mass).

The Messe de Nostre Dame consists of 5 movements, the Kyrie, Gloria, Credo, Sanctus, and Agnus Dei, followed by the dismissal Ite, missa est. The tenor of the Kyrie is based on Vatican Kyrie IV, the Sanctus and Agnus correspond to Vatican Mass XVII and the Ite is on Sanctus VIII. The Gloria and Credo have no apparent chant basis, although they are stylistically related to one another.

Machaut's Messe de Nostre Dame is for four voices rather than the more common three. Machaut added a contratenor voice that moved in the same low range as the tenor, sometimes replacing it as the lowest voice.

In the liturgy of the Mass, the items of the Ordinary are not performed consecutively, but are separated from one another by prayers and chants. Machaut's unification of these items into an artistic whole is the earliest instance of an Ordinary of the Mass setting that is stylistically coherent and was also conceived as a unit. This gesture imposed on the Ordinary a previously unconsidered abstract artistic idea, and potentially influenced composers throughout the ages to continue setting the Ordinary to stylistically coherent music.

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