The origins of marriage

Marriage's primary purpose was to bind women to men, and thus guarantee that a man's children were truly his biological heirs. Through marriage, a woman became a man's property. In the betrothal ceremony of ancient Greece, a father would hand over his daughter with these words: "I pledge my daughter for the purpose of producing legitimate offspring." Among the ancient Hebrews, men were free to take several wives; married Greeks and Romans were free to satisfy their sexual urges with concubines, prostitutes, and even teenage male lovers, while their wives were required to stay home and tend to the household. If wives failed to produce offspring, their husbands could give them back and marry someone else.

As the Roman Catholic Church became a powerful institution in Europe, the blessings of a priest became a necessary step for a marriage to be legally recognized. By the eighth century, marriage was widely accepted in the Catholic church as a sacrament, or a ceremony to bestow God's grace. At the Council of Trent in 1563, the sacramental nature of marriage was written into canon law. 

Church blessings did improve the lot of wives. Men were taught to show greater respect for their wives, and forbidden from divorcing them. Christian doctrine declared that "the twain shall be one flesh," giving husband and wife exclusive access to each other's body. This put new pressure on men to remain sexually faithful. But the church still held that men were the head of families, with their wives deferring to their wishes.