In 1554, he was arrested and imprisoned, presumably for these illicit printing activities.[3] Under Queen Elizabeth I, Day returned to his premises at Aldersgate in London, where he enjoyed the patronage of high-ranking officials and nobles, including William Cecil, Robert Dudley, and Matthew Parker. With their support, he published the Book of Martyrs and was awarded monopolies for some of the most popular English books, such as The ABC with Little Catechism and The Whole Booke of Psalmes.[4] Day, whose technical skill matched his business acumen, has been called "the master printer of the English Reformation".[5]