Bibliothèque nationale, Paris, shelf mark MS lat. 17294 is a remarkably beautiful book. It is an early fifteenth-century breviary, and it happens to contain liturgical material for the celebration of St David's Day. The most obvious characteristic of the book is that it is richly decorated on every folio. Art historians have naturally examined it and Victor Leroquais and Eleanor Spencer have written about it, but other than that it has been recognized as being of Sarum use, its liturgical features continue to require further investigation. As observance of the feast of St David on 1 March was made obligatory in the province of Canterbury in 1398, service books of British origin produced after this time normally contain a reference in the Kalendar along with instructions in the Sanctorale as to how it was to be celebrated. This particular breviary being no exception, it became one of many witnesses to St David's Day celebrations during the period of a hundred and forty-five years before King Henry VIII's injunction suppressing the worship of non-scriptural saints.

My aim in this essay is to draw attention to the Parisian source and to make observations on noteworthy features. Matters that arise in this kind of investigation will be touched upon, in order to be able to view the manuscript in context. These include referring to material for celebrating St David in a typical book of hours, regulations for the feast of St David, in particular with regard to the matter of ruling, and I refer to statutes concerning liturgical books in general.