In Roman Catholic tradition, the requiem mass is a ritual celebration of the Last Supper within the context of a funeral. The requiem mass is distinguished from masses for other occasions by the presence of a specific text, laid out in the missal of Pope St. Pius V from 1570, and the absence of the more joyful parts of mass, such as the Gloria, and the Credo (Cave). The missal of Pope St. Pius V contains the prayers for all masses that would be conducted during the year in the Catholic Church. This was in accordance with the Council of Trents (1545-63) wishes that local variations on the mass would be halted and that a standardization of the mass be enforced (Wolff, 66). The missal requires that the musical portion of the requiem mass follow certain texts. Out of the ten sections listed in the missal, seven are most commonly put to music: the Introit, Kyrie, Sequence (Dies Irae), Offertory, Sanctus, Agnus Dei, and Communion. Composers over the centuries have decided to combine certain section, such as the Introit and the Kyrie or the Agnus Dei and the Communion.The first reference to a complete requiem composition prior to the 16th century is located in the will of Guillaume Du Fay (1397-1474). His composition has never been recovered. Johannes Ockeghem () completed his requiem composition before 1500. Other requiems from the 16th Century include Brumel, Prioris, Palestrina, Anrio, and Victoria. Between 1470 and 1600 forty-one requiem mass compositions have been preserved. The Baroque period brought about new and exciting changes for the musical world. Requiems from this period include Bournonville (1619) and Brunelli (1619). Claudio Monteverdi, Giovanni Grillo, and Francesco Usper collaborated to produce the requiem that performed at the funeral mass of Cosimo II de Medici in 1621. This requiem was the first to include instrumental sections. The Baroque composers produced 325 known requiem compositions. The Classical...
