Abstract
There are no extant sources of the complete Prague Office of St Adalbert dated from before the 14th century. Nonetheless, some of the antiphons of the office have stylistic features that indicate a much earlier date of origin.
That hypothesis has now been confirmed by the surprising discovery of a fragment from the 11th century at the Austrian National Library in Vienna (Österreichische Nationalbibliothek in Wien). The enormously valuable discovery of this fragment opens up new perspectives on the origins of the Prague Office of St Adalbert and on the overall context of liturgical chant in medieval Bohemia.