We often read that marriage has traditionally been a religious ceremony and therefore, we cannot separate religion from marriage. We should "get the state out of marriage" back to where it used to be when it first started.
However, that belief is mistaken, as is demonstrated in Danny Danziger and John Gillingham’s book, "1215: The Year of Magna Carta."
In medieval Britain, marriage was an arrangement between two families, and the Church only became involved in it around the year 1200.
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Marriage had originally been a purely secular affair - one for arrangement between the two families concerned - but it was one that the Church was now increasingly trying to influence. In 1200, for instance, an English church council held at Winchester decreed that no marriage should be contracted without a public announcement in church on three occasions and that no one should be joined in matrimony except publicly in front of the church and in the presence of a priest.
This edict ran into problems when the Church effectively went on strike between 1208 and 1214 due to an ongoing argument between Pope Innocent III and King John about who the archbishop should be. No mass was celebrated in Britain for six years.
The interdict meant that for six years there were no marriage services in church, but this did not prevent weddings taking place. The decrees of the council of Westminster tell us how the Church would have liked marriages to be celebrated, but that is all. In fact the Church had already decided that what made a marriage valid in law was the freely given exchange of marriage vows between two people of age (that is, twelve or over) who were not within the prohibited degrees. Twelfth-century canon law defined the prohibited degrees of kinship as meaning that any couple who were within seven degrees, that is who shared great-great-great-great grandparents, could not enter into a valid marriage. However, this created an absurd situation in which virtually every marriage was vulnerable to the charge of incest. At the Lateran Council of 1215 Innocent III tackled the problem by reducing the number of prohibited degrees from seven to four.
For a marriage to be valid it did not matter where the vows were exchanged. It did not have to be at the church door, though doubtless most people liked a traditional wedding. It could just as well have been in a garden, in a shop, in a tavern or in bed. No witnesses or public ceremony were necessary. The couple who freely exchanged vows did not need, though it was undoubtedly desirable, the consent of their parents, guardians or lords. The canon law of marriage - the lover’s charter, it has been called - remained the law in England until 1753, when Parliament decided that all marriages had to be performed by a clergyman and that no one under the age of twenty-one could marry without the consent of parents or guardians. After 1753 the young eloped across the border to Gretna Green where the old law remained in force.
Many hundreds of years after the events in this book, British immigrants came to America and helped to shape the culture and the laws here. Albion’s Seed: Four British Folkways in America, by David Hackett Fisher, tells the cultural history of how these immigrants brought their traditions from various parts of the island which remained and helped shape cultural expectations in the United States. The history related here is of course from much later than 1215, but relates to marriage within the early history of the United States. In his discussion of early New England, Fisher states,
The Church of England had taught that matrimony was a sacred union that must be solemnized by a priest. Anglicans also insisted that after the sacred knot was firmly tied, it could never be "put asunder" by mortal hands. Exceptions were allowed for monarchs and great lords, but for ordinary English men and women there was virtually no possibility of divorce in the seventeenth century. The Puritans of New England rejected all of these Anglican ideas. They believed that marriage was not a religious ceremony but a civil contract. They required that this covenant must be "agreed" or "executed" (not "performed" or "solemnized") before a magistrate, and not a minister. They also insisted that if the terms of the marriage covenant were broken, then the union could be ended by divorce. These attitudes became the regional marriage customs throughout New England.
In some other parts of the United States which had other, non-Puritan immigrants, religion was more commonly a part of the marriage ceremony.
The bride and groom in Virginia were often united in two ceremonies - both of which were condemned in Puritan New England. The first was a Christian ceremony, which was solemnized sometimes in a church or more often in the bride's home, but always by a minister according to the laws of the Anglican Church and the Book of Common Prayer. The other ceremony was an ancient pagan practice in which the bride and groom were made to jump over a broomstick. This ritual had long been observed throughout Britain and much of western Europe, and especially in the kingdoms of Wessex and Mercia.
Jumping the broom was a common practice in the South and as Fisher states, "For black slaves, it was the only type of marriage ceremony that was permitted, and rapidly acquired a special meaning in Afro-American culture."
In Quaker areas such as Pennsylvania, the marriage ceremony was again different.
A proper Quaker wedding had no fewer than sixteen stages. When a man and woman agreed to marry, their first formal step was to consult their parents, which sometimes they did even before settling the question among themselves... If all agreed, the couple jointly announced their intention to marry before the women's meeting. After an interval which gave the community time to digest the news, a female Friend formally sent a notice to the men's meeting. The intending couple then presented themselves before the men's meeting and announced that "with the Lord's permission and Friends' approbation they intend to take each other in marriage." ... [Further meetings, announcements, and agreements are described, then...] On the appointed day, the marriage at last took place. It proceeded very much like a meeting for worship. People entered quietly and sat in silence, sometimes for very long periods. Those who wished to speak could rise and say what they wished, and some were moved to speak at length. Then, almost as an anticlimax, the intended couple quietly declared their agreement to marry, and spoke promises to one another in words of their own invention. After this exchange, everyone sat silently for a while, and quietly went home.
Quaker wedding ceremonies took place in the house of worship, but did not involve making vows before a minister, rather before the group as a whole. These ceremonies are similar to this description today; I attended one a few years ago.
The idea that marriage has always, until the 20th century, been purely a Christian and religious institution is simply false history. Marriage customs and laws were in very early times secular, but became part of religious tradition over time. Marriage customs have also changed over time; allowing same sex couples to marry is another change within an historical framework of change.