From “A History of the Wife” by Marilyn Yalom:

At the peasant level, marriage was largely an economic arrangement that took place when two people were able to put together sufficient resources for joint survival. A bride’s dowry consisting of money, goods, animals, or land was essential to the founding of a new household... it was understood that if the bride’s family did not pay the groom what had been promised, the marriage was essentially null and void.

Still, we should not assume that peasant marriage was only a legal and economic affair. Mutual attraction could also play its part. Country youth found opportunity in forests, fields, and haystacks for premarital dalliance. Numerous couples did not bother to marry until the female had proved her fertility by becoming pregnant.

From the chapter “Wives in Medieval Europe, 1100-1500”

According to the same book, it was from the 1500s onwards that love began to acquire a much more important factor in marriage arrangements, more so in England than in continental Europe.

By the turn of the seventeenth century, English conduct books assumed that a man would choose a wife “according to his own heart”, and that a woman, though not so free as a man, had the right to respond to male initiative. Montesquieu in the eighteenth century and Engels in the nineteenth contrasted the freedom of English daughters to marry “according to their own fancy, without consulting their parents” with the situation of Europeans, who were required by law to obtain their parents’ consent.

From the chapter “Protestant Wives in Germany, England, and America, 1500-1700”

According to the book,

Most social historians agree that modern Western marriage emerged in the period between the American Revolution and around 1830. During those fifty years, love became the most celebrated criterion for choosing a spouse, even if property, family, and social status continued to weigh heavily in the decision.

From the chapter “Victorian Wives on Both Sides of the Atlantic”