Jungmann, Josef A., S.J. "Chapter Eighteen: The Latin Liturgies." The Early Liturgy to the Time of Gregory the Great. (translated by Francis A. Brunner, C.S.S. R., Notre Dame, Indiana: University of Notre Dame Press, 1959, pp. 227-237.
Jungmann observes that even through the sixth century the centralized organization of liturgy in Rome was not as strong as it is today (Jungmann 1959, 227). In many cases the unity of the Latin langauge was the primary way in which the Church was held together. In general, though, liturgical patterns separated into two regions: that of Rome and North Africa, and that of the rest of Europe.
In the Gallic liturgies, found through much of Western Europe, the basic liturgy was held largely in common, but the forms of the prayers varied from one country to another (Jungmann 1959, 228). The prayers also varied from season to season, unlike those in Rome. Jungmann reviews four liturgical streams in turn: "the Old Spanish, the Gallican, the Celtic, and the Milanese" (Jungmann 1959, 229).
The Old Spanish liturgy, also known as the Mozarabic liturgy, developed and stabilized in the sixth century and featured prayers influenced by the Arian controversy (Jungmann 1959, 229). The region had endured particularly virulent opposition by the Arian Visigoths, who had engaged in persecution of the Catholic Christians. Prayer formulations in particular were used to reject Arian doctrines and to affirm the consubstantiality of the Father and the Son (Jungmann 1959, 230).
The Gallican liturgy, specifically in use in the ancient Frankish territory, was also growing in the fifth and sixth centuries, though most of the documents are from the seventh century (Jungmann 1959, 231). Jungmann observes that rather than using one passage of Scripture as a foundation for a liturgical element, the Gallican liturgy gathers several passages from various locations. As with the Old Spanish liturgy, there are strong anti-Arian elements (Jungmann 1959, 232).
The Celtic liturgy was found especially in the British Isles. Jungmann notes that the Celtic languages were not written languages, and that the liturgy maintained use of the Latin language (Jungmann 1959, 232). We have relatively little documentation of this liturgy except near the end of the seventh century.
The Milanese liturgy, unlike the others, is still in use in an entire ecclesiastical province (Jungmann 1959, 232). In its modern form it has incorporated many elements of the Roman liturgy. However, many of the prayers show their non-Roman roots.
The Romano-African liturgy differs from the Gallic forms. Though we have no comprehensive record from North Africa, many details survive as mentioned by Tertullian, Cyprian, and Augustine (Jungmann 1959, 234). The structure appars very consistent with that used in Rome. Jungmann points out that the Roman liturgy as it developed was consistent with the third century Greek liturgy, but that it is in Latin, rather than Greek. Jungmann surveys this liturgy in some detail as it is the foundation for what he discusses in the remainder of the book (Jungmann 1959, 234). The source for this study is a "Sacramentarium," which is the book of liturgy used by a priest officiating at a service. We have a seventh century example in the Sacramentarium Leonianum, whith over three hundred mass formularies, mostly for feasts and martyrs' days (Jungmann 1959, 235). A second source, from much the same time period, is the Sacramentarium Gelasianum (Jungmann 1959, 236).