The Church of England came into being because of a man's desire to have a son.
After more than 20 years of marriage, Henry VIII had been able to produce only one legitimate child. However, that child was a daughter. People at the time remembered the so-called War of the Roses, in which one side of a family fought the other for the throne. Henry feared that if he did not have a son to reign after him, the country would collapse into war again.
Big problem: Henry's wife was Katherine of Aragon, who was the daughter of Ferdinand and Isabella and aunt of the Holy Roman Emperor. In other words, a very strict Catholic who did not believe in divorce. So Henry could not remarry, and the woman he was hot for, Anne Boleyn, would not sleep with him without a ring on her finger. Henry's advisers, who leaned toward protestantism, suggested that he exert his power by breaking ties with Rome and declaring himself the head of the church in England. That way, he could get his divorce, marry Anne, and finally try for a legitimate son. His plan was not totally successful, but that's another story.
How is this relevant to the novel in question? When England broke with the Roman Catholic Church, the Church of England was not the only nonCatholic church available. The Protestant Reformation spread across Britain. People were able to form groups of likeminded worshipers, and new forms of worship, such as Puritanism, began to appear.
Visit the sites below for more info.