In my article on white weddings, I cited a portion of the Sarum rite of marriage. One of the many customs in this rite that stuck out to me was that the groom is instructed to place the ring on the bride’s right hand. Now, of course, our current custom in America is generally to put the ring on the left hand, so I did some reading to figure out how we got from the right in the Middle Ages to the left in the 21st century.
In England, the switch from right to left came at once, with the issuing of the Book of Common Prayer in 1549. Thomas Cranmer, first Protestant Archbishop of Canterbury, took advantage of Henry VIII’s death and the reign of the boy-king Edward to get rid of the Roman Mass entirely and impose his own ideas for worship across the island nation. The Book of Common Prayer instructed grooms to place the ring on the left hand from that point onward. I can’t find a single source explaining why this change happened. I do, however, know that the episcopal ring was everywhere prescribed to be placed on the right hand of a bishop to represent his marriage to his church. I saw one source stating that Saint Charles Borromeo, Archbishop of Milan during the Counter-Reformation, criticized the practice of wearing wedding rings on the right hand because it imitated the practice of bishops.
Elsewhere, I’ve seen Eastern Orthodox sites claim that they’ve always worn rings on the right hand, and that the West has erred in switching to the left because the father in Christ’s parable about the prodigal son put a ring on his son’s right hand; therefore, the right hand is Biblical. Yet other sites claim that in some European countries such as Germany, wearing on the right hand is still customary, regardless of religion. In the Netherlands, apparently Catholics wear rings on the left while Protestants wear it on the right. The whole matter is terribly confusing, so I’ll have to chalk it up as a non-essential issue, though one who follows medieval custom will probably lean more toward favoring the right hand.