The Office for Corpus Christi was composed by Jean du Mont-Cornillon at the instigation of Juliana du Mont-Cornillon, founder of the Corpus Christi Office. Barbara Walters among others suggest that Juliana played a more significant role in the creation of the Office than previously acknowledged, citing passages in Juliana's vita that emphasize her role as intellectual author and editor. Written for the diocese of Liège (1246), the Office was used elsewhere as well. The Office of the Conception is found in Analecta hymnica vol. 5, #12 (pp. 47-50). The Maternus Office is found in Analecta hymnica vol. 28, #21 (pp. 61-63) and LMLO-MF31. The Office of Bartholomew is in Analecta hymnica 5, #50 (pp. 148-50) and LMLO-BA81. Most of the chants in this manuscript are not found in CAO.
Any non-CAO chants also found in Tongeren, Onze-Lieve-Vrouw-Kerk, 63 and 64 are given the same identification numbers in the Den Haag file, since these manuscripts all represent the liturgy of the same church. Similarly, the differentia codes used for Den Haag are consistent with those of the Tongres 63 and 64; the differentiae are labelled with a letter-number combination (the letter indicates the final pitch of the differentia, and the number is arbitrarily assigned).
The remaining contents of the manuscript, which are not contained in the index, are as follows:
Ff. 1r-39r, partial martyrologium (Usuardus, O.S.B.); 40r-51v, Necrologium ecclesiae S. Mariae Tongrensis (1 January to 10 April); 52r-63v, lections for Corpus Christi and its octave (attrib. Thomas Aquinas, 14th century); 64r-67r, lections for Barbara with a collecta and incipits for Mass; 67v-71v, Feast of Anna (incomplete), containing items for both Mass and Office; 72r-74v, lections and Mass for Conception (no music); 97r-100v, lections and Mass for Dominic; 111r-115v: Vita beati Francisci abbreviata, divided into lessons for the feast of Francis; 122r-127v, lections for Conception.
Boeren (1988) identified these items. Our Lady’s church in Tongres is as old as the 4th century, the period of Bishop Servatius. A chapter was founded in the 9th century. At the end of the 14th century the famous Radulphus de Rivo became Dean of the chapter, and subsequently carried out many liturgical reforms, necessitating the preparation of new liturgical books. Therefore, although we possess many liturgical manuscripts from the late-14th or early-15th century, most of the older ones do not survive. Den Haag KB 70 E 4 thus contains Our Lady's oldest liturgical documents.
Most of the manuscripts of Our Lady's church are preserved there, including the following:
Graduale, MS 57 (late-14th century).
Antiphonarium hiemale, MS 63 (late-14th century).
Antiphonarium hiemale. MS 64 (late-14th century).
Liber Ordinarius, s.n., 1435-1436, edited in Lefèvre, Pl.F. L'Ordinaire de la collégiale, autrefois cathédrale, de Tongres d'après un manuscrit du xve siècle. I: Le Temporal, II: Le Sanctoral. Louvain, 1967-8.
Intonation book for the Office, MS 37 'ad usum succentoris', damaged and in poor condition.
Processionale, MS 55, (olim 37), Hufnagelschrift on red staves (14th-15th century).
- Boeren, P.C. et al. Catalogus van de liturgische handschriften van de Koninklijke Bibliotheek, pp. 6-11. Den Haag: 1988.
- Corswarem, P. de. De liturgische boeken der kollegiale kerk van O.L.Vr. van Tongeren voor het Concilie van Trente . Gent: 1923.
- Dreves, G.M. ed. Analecta Hymnica Medii Aevi. 55 Volumes. Leipzig: 1886. Reprint. Frankfurt am Main: Minerva, 1961.
- Hughes, Andrew. Late Medieval Liturgical Offices: Resources for Electronic Research. Subsidia Mediaevalia. Vol. 23. Toronto: Pontifical Institute of Medieval Studies, 1994.
- Barbara Walters. "Laureata plebs fidelis: A Victorine Sequence from the Feast of Corpus Christi in the Diocese of Liège." In Music, Dance, and Society: Medieval and Renaissance Studies in Memory of Ingrid G. Brainerd, edited by Ann Buckley and Cynthia J. Cyrus, 71-88. Kalamazoo: Medieval Institute Publications, 2011.
- Barbara Walters, Peter T. Ricketts, and Vincent Corrigan. The Feast of Corpus Christi. Philadelphia: Penn State University Press, 2006.