Abstract
The Cividale liturgical manuscripts preserve notated examples of cantus planus binatim, two voiced polyphony progressing in rhythmic unison following a cantus firmus based on an established chant. Contrary to common theory that this repertoire can be distinguished from mensural polyphony along class and economic lines, evidence suggests that this repertoire reflects local musical practices unrelated to social hierarchy. The temporal development of the repertoire as represented by the Cividale manuscripts supports the theory that this was an oral repertoire that was potentially improvised, and as illustrated by quotations in Quem ethera et terra, drew upon established formulas embedded in the repertoire of its performers.\r Cividale 57 additionally contains two polyphonic hymns, Letare felix civitas and Iste confessor, which were added to the manuscript after its original compilation. I transcribe and analyze these hymns with emphasis on Iste confessor, relative to the Dufay Hymn cycle. I trace the monophonic tradition of the different melodies to illustrate stylistic similarities between the versions and cantus planus binatim. Research into the history of the city of Cividale and its primary liturgical feasts suggests that the hymn is in Cividale as part of the celebration of Vespers for either Saint Martin or Saint Donatus.\r Concordances between CF57 and the Apt manuscript suggest a connection between Cividale and Avignon concurrent with the Schism. Liturgical rubrics, the hierarchy of clerks, and the Hymns of the Apt manuscript illustrate that there was an established tradition in Avignon for singing Office hymns resembling cantus planus binatim. Pope Gregory XI returned to Rome establishing a musical center in the tradition of Avignon. Pope Gregory the XII traveled to Cividale for the Council of 1407, providing evidence for a possible chronology for the Cividale version of Iste confessor relative to the Dufay Vespers cycle. The stylistic similarities between the Hymns of Avignon and the Office Responsories of Cividale indicate that there was an established central tradition for the singing of simple polyphony during the celebration of the Office during the Schism. This tradition was influenced by local musical traditions and local sacred celebrations.