Protestants who fled England during the reign of Mary Tudor settled in a number of cities on the Continent. Those who went to Geneva at the invitation of John Calvin have become known as the most radical voices for reform of the Church of England during the Elizabethan Settlement. Many scholars have called them 'puritans.' Pilgrimage to Puritanism is a comprehensive study of these English Protestant refugees: who they were, what they published while in Geneva and later during Elizabeth's reign, the nature of the refugee church they established under Calvin's tutelage, and the theological and political thought that became pivotal in sixteenth-century English Puritanism.