This is a collation of three works found in the Old Hall Manuscript (early 15th century).

The two trope-motets in this are by Thomas Dammett (c. 1390-1436/7) and Nicholas Sturgeon (d. 1454). These two motets use as their tenor part a section of the Sanctus text, which is treated isorhythmically. In the first case (OH 111), the tenor part is in fact a slightly troped form of the Sanctus text. The fact that this ("Benedictus Mariae filius qui ve-") breaks off at exactly the same moment the the other motet (OH 113) picks it up ("-nit in nomine Domini") made me want to join the two motets together and create a full cantus firmus statement: this seems like it could have been the intention of the collator of the manuscript.

In order to achieve this, the second motet has been transposed so its tenor part stays in the same pitch as the first - leading to a few awkward range issues.

Finally, this collated trope-motet needed a framework of the main Sanctus itself, to go around it. There is no particular reason to choose any particular setting of the rest of the Sanctus, other than that it would be one using the same plainchant cantus firmus. I have picked one of my favourites from the Old Hall manuscript (OH117) for the job here, and this is by the great Leonel Power (d.1446). It is a setting for somewhat virtuoso singers!

Incidentally, these are likely to be the motets described as being sung following the battle of Agincourt in 1420.

NOTE: The mp3 here does not include any of the accidentals suggested as musica ficta above the staff!