Nothing is more essentially Catholic than settings of the Mass, a point which would not have been lost on Elizabeth I’s secret police, dedicated as they were to tracking down and harassing believers in the old religion. No one had set these texts in England since Queen Mary’s reign some decades before (and would not do so again for three hundred years), so Byrd’s trilogy stands isolated in time. But the really daring part of the story is that he published this music, admittedly in small volumes without title-pages, but with his name clearly given. Having taken such risks it is not surprising to find that the music itself is deeply expressive. The four-part Mass is perhaps the most personal as well as the earliest of the set, almost certainly written in 1592. It retains some techniques from the distant past, such as blurring the boundaries between the tenor and alto parts, yet there are moments of intensity – like the ‘dona nobis pacem’ – which Byrd never surpassed in all his later music.
from notes by Peter Phillips ę 2007