Charles M. Atkinson, Ph.D. 1975

Advisor: Calvin Bower

Dissertation Title: The Earliest Settings of the Agnus Dei and Its Tropes

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Dissertation Abstract:

In the earliest musical manuscripts that contain it, the Agnus Dei appears in conjunction with other texts and music. Although these texts with music have traditionally been called “tropes,” scholars have recently begun to question the validity of this concept as applied to the early Agnus Dei repertoire.

In an effort to clarify the relationship between the Agnus Dei and its supposed tropes, the present dissertation first traces the history of the text of this chant from its scriptural appearance in John 1:29 through its earliest liturgical use in the Gloria, its use in the litany of saints, and its introduction into the Roman Mass as a chant to accompany the Fraction. Evidence drawn from the Liber pontificalis, the Ordines romani, Carolingian expositiones missae and sacramentaries indicates that the Agnus Dei was introduced into the Mass no later than the pontificate of Sergius I (687-701). This evidence further suggests that a threefold repetition of the verse Agnus Dei, qui tollis peccata mundi, Miserere nobis was probably the standard text for this chant by the mid-ninth century, if not earlier. The same sources also assign the singing of the Agnus Dei to the Schola cantorum at a very early date.

The central portion of the dissertation focuses upon three settings of the Agnus Dei that are disseminated in both east- and west-Frankish manuscripts dating from the tenth century: Qui sedes, Quern Johannes/Cui Abel, and 0 amnos tu theu (the Greek Agnus Dei). Their manuscript tradition, textual sources, and position during the liturgical year would indicate that these items may be among the oldest in the entire repertoire. Examination of these settings reveals that the standard text of the Agnus Dei as given in non-musical sources can be distinguished from the trope verses that accompany it: The earliest preserved Agnus Dei melody displays a threefold repetition in numerous early manuscripts; several different sets of verses can appear with a given Agnus Dei melody; the musical style of these verses contrasts with the style of the Agnus Dei melody they embellish. Indeed, the verses resemble each other in style more than they resemble the Agnus Dei melody with which they are sung. On the basis of this evidence we may consider these additional verses “tropes”—just as they are labeled “tropi” in the manuscripts themselves. 0 amnos, as part of the Missa graeca, is a special case. Though not a “trope,” it is occasionally treated as one even in medieval sources.

The final section of this study treats the remaining corpus of tenth-century troped settings of the Agnus Dei, those disseminated only within a specific geographical area. Analytical criteria established in earlier chapters are incorporated here in an effort to develop a system of chronological ordering that might serve as a basis upon which the stylistic evolution of both the Agnus Dei and its tropes may be studied. Within the tenth-century corpus of tropes one finds that the earliest layer includes items whose texts are for the most part non-poetic and whose musical style contrasts noticeably with the Agnus Dei they embellish. A higher percentage of poetic verses characterizes later tenth-century tropes; moreover, the musical style of these tropes moves closer to that of their associated Agnus Dei melodies. In some cases melodic similarities are reinforced by the sharing of melodic incipits and internal phrases by both trope and base chant. Examples of prosula and contrafactum also appear in the later segment of the repertoire.

Two appendixes present inventories of Agnus Dei settings in the 41 tenth- and eleventh-century manuscripts that formed the primary basis for this study and provide diplomatic transcriptions of the tenth-century corpus of tropes as they appear in selected manuscripts dating from the tenth to the thirteenth centuries.

Dr. Atkinson is currently Professor Emeritus of Music at the Ohio State University, where he was named a University Distinguished Professor in 2013. His work has focused on early music from ancient times to the Renaissance.