About
Our current calendar only dates to 1572, when Pope Gregory XIII issued the bull that gave us the Gregorian calendar. During the previous centuries, the calendar had been proven imprecise and by the mid-sixteenth century there was a difference of ten days between it and the actual position of the moon. This was not the first time either. Over the course of Antiquity and the Middle Ages the calendar had proved faulty a number of times, and continued to be corrected by newer calculations, shifting between 19-year (Alexandrian), 84-year (Roman, Insular), 19/532-year (Dionysian/Bedan) tables. While we now have a universally accepted calendar, there is still no concensus about the calculations for the most important Christian feast of the year, Easter!
MS Paris, BnF, lat. 10837, early eighth century The image on your left is from the Calendar of St. Willibrord (d. 739), one of the earliest insular calendars that has survived. The calendar in this famous codex was brought to… Tallaght, early ninth century Roughly a century after Laurentius copied his martyrology, two martyrologies were produced in the monastery of Tallaght. The first, known as the Martyrology of Tallaght, is an adaptation of an abbreviated version of the Martyrologium Hieronymianum… TCD MS 11463, Regensberg, Germany, ca. 1040-1075 AD Over time, outdated martyrologies were sometimes recycled, so that evidence of their transmission is often lost or obscured. It is all the more fortunate, therefore, when fragments resurface. This single leaf from… TCD MS 50, Llanbadarn Fawr, twelfth century This small Welsh psalter contains a copy of the Hieronymianum which may be derived from an Irish exemplar. It was written at Llanbadarn Fawr in Ceredigion and belonged to Rhygyfarch ap Sulien (c…. TCD MS 194, All Hallows, London, ca. 1250-1300 This composite English book belonged to the thirteenth-century community of All Hallows in London and contains, beside a calendar and accompanying martyrology, a number of tracts on time and rhetoric, as well… TCD MS 97, Dublin, 13th-14th century With MS 97 we enter the era of the Anglo-Irish monastic houses. The martyrology in MS 97 was copied for the Augustinian canons of St. Thomas (hence modern Thomas Street). The text is based… The Antiphonary of Armagh TCD MS 77, Armagh, mid 15th century This and the following antiphonal are both examples of the Irish use of the rite of worship, which had been declared as the practice of the churches of Dublin… TCD MS 84, Trim, 15th century This psalter belonged to St. Mary’s Abbey in Trim Abbey, which is believed to have been the first of a handful of foundations which adopted the Arrouaisian Rule. It contains special services for St…. NLI G 27 (Shorter version), 17th century In the early seventeenth century, the Franciscan college of St. Anthony in Louvain was engaged in a project seeking to gather and publish all of Ireland’s textual heritage, which was in danger of… Liège, 1255-1265 AD Office books and calendars were often highly tailored to the community which produced it in both content and form, and, as he have seen, reflect the habits and interests of their users. This Mosan psalter-hours, executed in…
The Earliest Calendars and Martyrologies: Willibrord
The Tallaght Martyrologies
The Regensberg Fragment
The Rhygyfarch (al. Ricemarch) Psalter
The Calendar and Martyrology of All Hallows
The Calendar and Martyrology of St. Thomas Abbey
Two 15th-century Antiphonaries
An Arrouaisian Psalter from St. Mary’s Abbey, Trim
The Martyrology of Donegal
A Psalter-Hours from Liège