The Requiem Mass is one of the most frequently performed Masses of the Medieval period. It is this mass that forms the centerpiece of Gloriae Dei Cantores Schola's acclaimed recording Gregorian Requiem. Not only are two traditional masses included, but there are antiphons for the vigil prior to the funeral, antiphons changed in the church beforehand, as well as chants sung as the casket leaves the church. Included also is the sequence Dies irae, dies illa, best known for it's inclusion in more modern Requiems such as those by Mozart, Verdi, and Durufle. Thus, this recording presents a medieval funeral mass, as it would have been chanted in the fourteenth century.