The Calendar of St Willibrord is one of the most important manuscripts to have survived from the early middle ages. The personal liturgical calendar of Willibrord, the English missionary from Yorkshire who, with papal authority, became in 695 the apostle of Frisia and the first bishop of Utrecht, it is one of the earliest surviving examples of this type of liturgical book, and certainly the earliest to have survived from Anglo-Saxon England. The book is elegantly written in a high grade of script, but has been annotated by members of Willibrord's household (and possibly by Willibrord himself). As such, the manuscript provides a lucid index to those saints who were worshipped in Willibrord's own household; strikingly, in addition to commemorations of saints who were widely culted in early eighth-century Europe, the `Calendar' includes little-known saints who were culted in places as far away as Constantinople and Syria, and is thus a crucial witness to an important early phase of English Christianity.
A full facsimile of the manuscript itself is accompanied by a detailed introduction and commentary on the saints commemorated by H.A. WILSON (d. 1927), one of the country's outstanding liturgical scholars.