Early 15th-Century Pairings of the Sanctus and Agnus Dei, and the Case of the Composer “Bloym”

Self-contained pairings of the polyphonic Sanctus and Agnus Dei (as distinct from the Gloria and Credo) appear to have been something of a rarity in the early 15th century, both on the Continent and in England. In their catalogue of 15th-century English liturgical music, Gareth Curtis and Andrew Wathey list just five firm Sanctus-Agnus pairs for the period ca. 1400–ca. 1440. Yet examination of these alleged pairs suggests that the status of all but one of them is in some degree open to question. Curtis and Wathey's catalogue also includes a number of movements that have been paired either by 15th-century scribes or by modern commentators but that have so far failed to convince. Among them is a group of eight closely related movements contained in a layer of the two oldest Trent Codices (MSS 87 and 92), which comprises four possible pairs. Investigation suggests that all eight movements are probably the work of the same composer, “Bloym,” whose name heads one of the Sanctus settings; that in the process of transmission a number of the movements became wrongly associated; and that by realigning them new and more plausible pairings can be established. The establishment of connections between one of these pairings and a Credo attributed to Bloym in the same Trent layer raises the possibility that all three movements may have been conceived in conjunction with one another, and may therefore form a partial or incomplete cycle.