Changes in the English church begun during Henry VIII’s reign, initially more concerned with economics and politics than with theology, turned during Edward VI’s reign into a wholesale assault on the “Old Religion.” The apparatus of the liturgy—including music books used in Latin services—and the institutions that had supported it were destroyed.
In the Catholic Book of Hours to the right, the iconoclastic fury of some reformers in England during this period is evident. The book is defaced; a reader has crossed out references to the Pope as well as to indulgences such as one earned by "say[ing] .iii. times the hoole salutacyon of our lady." Books of Hours—primers containing prayers for lay devotion—were Catholic "bestsellers."
After Edward’s death, Mary I reinstituted Catholic observance, while Protestants, now in exile, were absorbing practices of Calvin’s Geneva.
When she became queen, Elizabeth I re-established the Book of Common Prayer, and composers began creating music for an English church that would offer a distinctive blend of traditional and reformed practices.