During the reign of Mary Tudor, Queen of England from 1553 to 1558, Roman Catholicism became the official religion of the English state; and the English Crown once again recognized the authority of the pope. English Roman Catholics were jubilant while the Protestants believed that all of the gains of the English Reformation had been lost. The religious and even the political future of England was therefore clearly in the hands of Queen Elizabeth when she ascended the throne in 1558. She was subjected to strong pressure from both the Roman Catholics and the Protestants, and for some years the ultimate issue was in doubt. The religious decisions which were made in England during this period were, however, vital for the cause of Protestantism and of extreme significance for Roman Catholicism. Much of the historical writing which describes these crucial events is, naturally enough, the product of Protestant or Roman Catholic apologetic; and the subject is one which has need of calm and reasoned study as well as of ordered presentation.