It’s been 400 years since his death on 4 July 1623, but the composer William Byrd’s music is still a staple of religious services today. With an enormous output that ranged from simple choral pieces to complex exhibitions of polyphony, Byrd’s music was intrinsically linked to his own Catholic faith and to the Protestant religion that dominated during his life. We look at the impact of his work for his peers, and at the legacy he left for music lovers today.