The history of the full so-called "composite" calendar lies in the dark. The type often described in catalogues as having a saint for every day of the year.
My personal hypothesis is that the prototype, a version based on the liturgical calendar for Paris, was composed by a learned theologian at the University of Paris sometime during the 13th century, using a practise known as the "Martyrological Calendar" (i.e. a calendar extracted from a Martyrologium, like Martyrologium Usuardi). The oldest version from Paris known to me is the calendar in the Hours of Jeanne d'Evreaux (also called "Les Heures de Pucelles"). But by the time it was copied (c.1330) had the text already been corrupted on several points, which indicates that it must have passed through many hands before this.
The calendar as we know it from the Hours of Jeanne d'Evreaux continued to be modified on single days (example: St. Rigobert was inserted in some calendars on January 8th after his relics were received in Notre-Dame in Paris in 1362, causing a sliding or disrupting the following week, sometimes founding a new group. The later so popular and universal St.Yves (Ivo cf.) was canonized in 1347, another cause for variation around May 19th). The various corrections and many smaller or larger inherited errors continued in this way to split the tradition in several clearly separable branches, each forming a new group.
The significance of saints canonised in the mid fifteenth century for the dating of manuscripts is well known.
From time to time was the calendar revised by more or less competent scribes, but it was inevitable that a continuous row of changes took place during the course of the 15th century, resulting in a wide variety of models. None of them seems to have survived for more than a decade. As the number of surviving books of hours increase in the mid 15th century, is it possible to trace the itinerary of the later models, especially when they are used by scribes living and working in other cities in France.
The calendars from the period c.1450-1490 are the most valuable as sources for an analysis based on variants in the calendar, because there is a very good chance to find several products from the same scriptorium, with all the valuable information this can provide. After 1486 were the calendars spread as printed books, and the value thus reduced because similarity no longer is a proof of geographical proximity. In return does the printed sources provide a terminus post by their accurate dating.

This calendar-analysis was made in 1993 on basis of a database where only 42 full calendars of the Paris-type were entered (plus a few fragmentary sources, which explains that the total can be 44 in January). The statistics (number of occurrences in brackets) should convey a clear impression of normality versus individual variations. Single unique variants and trivial scribal errors are not included, which explains when the total is less than 42. With use of a combination of variants is it possible to distinguish various groups and sub-groups; the main groups can be dated within a decade, and the subgroups can be located to single scriptoria. The letters sometimes found with the variants below are internal sourcecodes. They mark a consensus in different groups. The letters "dm" f.ex. is an encouraging example of two calendars from related books of hours which match each other almost exactly with a combination of unusual variants in a subgroup. Both sources were illuminated by the so-called "Coevity-Master".
One of the main groups is here called the P-group (named after Paul Perdrizet, who published a calendar of this type).
All P-Group manuscripts are datable in the 1460'ies. A famous example belonging to the P-group, not included here, but reproduced in full by J.J.G. Alexander: "The Master of Mary of Burgundy" is the calendar in Oxford MS Douce 219 (Hours of Engelbert of Nassau) from the 2nd half of the 1460'ies. It illustrates how widespread the Paris model became everywhere in France during the 15th century. The scribe Nicolas Spierinck in Ghent used here a P-group calendar of a special version circulating in Northern France (from Burgundy), where he only changed two names, in order to make it appear to fit local use (Amand & Nicaise were rubricated).
Two of the sources included here falls outside the system, they are both from books of hours for the use of Amiens (letters H and R) and their calendars represent a tradition completely independent of the model from Paris (cf. The Amiens Calendar, July). There exist other local calendar-traditions of the composite type from different parts of France, but most are easily recognized by the large number of deviations from the general model (more than 60 days being different, cf. an example from Vannes (Dioc. Nantes, Brittany) under Thott 114 8°). Original local models have so many changes, that the sceleton of the liturgical calendar from Paris no longer is left intact. Another model, which strictly speaking is a completely independent composition is the T-Group, a calendar spread from Paris in Horae of Roman use, where it first was published in 1488 by the learned printer who probably compiled it (Jean du Pré: Horae ad usum Romanum, 20. Martius 1487 (1488 n.s.), and immediately after by Anthoine Vérard who plagiated Jean du Pré).
The T-Group is only represented with 2 sources here, but was very common after 1490-1500 in numerous manuscripts. The many T's below indicate its pricipal variants, cf. the other phenotype in KB Inc.2020.
Since this survey was made in 1995 have I entered a selection of more than 65 calendars on the Paris database, but the additional material has not changed the general statistical tendencies shown here.
All the calendars of this type from collections in Denmark will be supplied in full transcriptions, cf. the table of contents: Calendars.