While the history of different wedding traditions range from the obscure (who decided the couple should save the top tier of their cake?) to the downright creepy (was the best man really responsible for kidnapping the bride?), the end-of-ceremony kiss is one that's managed to retain its importance for generations. But the origins of the practice may not be entirely romantic; kissing has an historical element based in ancient Rome that's more transactional. "In an age of widespread illiteracy, kisses served to seal agreements; thus the expression "to seal with a kiss" and the "X" on the dotted line," writes Neel Burton, MD. "Couples got married by kissing in front of a gathered assembly, a practice that still carries on today."
Although the phrase "You may now kiss the bride" doesn't appear in the official sacrament of most religious ceremonies, some historians would argue that the big-day kiss first became a tradition in houses of worship. In Catholic ceremonies, for example, the priest would give the groom a "kiss of peace," which the groom would then pass on to his new wife. In other religions the kiss illustrates the often-invoked theme that "two become one." In some cultures—both ancient and modern—the wedding kiss is understood to be the couple's first, giving it a potentially awkward (but often rather sweet) quality.
Today, the ceremony kiss is as expected a part of the ceremony as the exchanging of the rings. And when it comes to royal weddings, it's dissected and discussed as much as the fashion. Will and Kate shared an instantly-iconic kiss on the balcony at Buckingham Palace, while Harry and Meghan made history as the first royal newlyweds to kiss on the steps outside St. George's Chapel; even Eugenie and Jack had their lip-lock put up for review by body language experts and royal watchers.
But what's the etiquette of a wedding kiss (assuming you're not a royal, of course)? The goal is "to show your love, without making your guests feel uncomfortable about the exchange," says etiquette expert Diane Gottsman, author of Modern Etiquette for a Better Life and founder of The Protocol School of Texas. "Remember there are tens or hundreds of people watching, including children, grandparents, and maybe your boss!" Her tips for a perfect wedding smooch: Skip dramatic movements, like kicks or dips; make sure you embrace each other in way that's "endearing and authentic," and not practiced or staged; and don't get too carried away: "Keep it G rated," she says. "You are in a church, not behind closed doors. A quick peck is not very affectionate, but a two-minute tongue twister is not appropriate either."