William Byrd

Wikipedia (1540-1623) [English. Renaissance.]
If you're just gonna listen to one: Ecco Virgo Concipet


Background

Like lots of people from more than five centuries ago, there's not a ton of historical information about William Byrd. What we do know is that he studied with Thomas Tallis, another of England's best-known Renaissance composers. We also know that he was a proud lifelong Catholic during one of the most violent period's of England's religious history, and this certainly cost him money and career advancement. Many of his most expressive compositions were written for the Latin rite, even though it was difficult for him to be a Catholic at that time. His numerous masses and motets and other sacred pieces form the main body of his work that exists today...

Mass for 4 Voices

Kyrie
Gloria
Credo
Sanctus
Benedictus
Agnus Dei

Other Sacred Music

Ave Verum Corpus
Tristitia et Anxietas
Ave Maria

Byrd also wrote some music for keyboard/harpsichord and "consort music," which is the precursor to what we think of as chamber music.

Consort Music

Fantasia #2 in G minor (Viol)
Diliges Dominum

And here's a link to an NPR story showcasing Stile Antico, performing four Renaissance works, two of which were by Byrd.