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The ancient Celts had a thing for trees.
No, they weren’t dendrophiliacs (as far as I know), but it’s clear from the historical writings of their ancient observers, like Pliny, that the Celts—and in particular, their religious leaders, the druids—held trees in high spiritual esteem. In fact, the very word “druid” is likely derived from the Old Celtic root words “deru,” meaning oak tree, and “weid,” meaning to see or know. Hence, “druid” could be loosely interpreted as “knower of the oak.”
Now, I know what you’re thinking: What the heck has that got to do with mistletoe? Or Christmas? Or kissing?
Hold your holly boughs. We’re getting there.
Pssst. Would you rather watch the video essay version of this post? 👇
First and foremost, you need to understand that mistletoe is a parasitic plant. It grows not from the ground, but from trees—including oak trees. To the ancient Celts, who, as we’ve already established, had a fondness for oak trees, mistletoe was a sacred plant. When winter came and the skeletal limbs of great oaks and other deciduous trees were left stark and barren, the mistletoe remained, verdant and vivacious.
To quote anthropologist Walter Evans-Wentz:
“The Celts may have viewed the mistletoe on the sacred oak as the seat of the tree’s life, because in the winter sleep of the leafless oak the mistletoe still maintains its own foliage and fruit, and like the heart of a sleeper continues pulsing with vitality. The mistletoe [was] thus regarded as the heart-centre of the divine spirit in the oak-tree.”
source: The Fairy-Faith in Celtic Countries (1911)
Or as historian J. A. MacCulloch puts it:
“The life of the tree was in the mistletoe, still alive in winter when the tree itself seemed to be dead. Such beliefs as this concerning the detachable soul or life survive in Märchen (folk tales).”
source: The Religion of the Ancient Celts (1911)
It is perhaps not surprising then, given the special status of mistletoe, that a druidic ceremony would develop around it, paving the way for our modern, Christmas kissing ritual. Granted, as you’re about to discover, the mistletoe ceremony of the ancient Celts was a bit lacking in the romance department.
The Celtic Mistletoe Rite: A Golden Sickle, a White Cloth, & a Pair of (Unlucky) Oxen
The earliest written account of the Celts using mistletoe as part of a religious ceremony comes from the famed Roman natural philosopher Pliny the Elder. Yes, before lending his namesake to a long-sought-for American beer, Pliny the Elder was famed for his first-century masterwork, Naturalis Historia. In it, he has this to say about the intersection of Celts, trees, and mistletoe:
“The Druids – for so [the Celts’] magicians are called – held nothing more sacred than the mistletoe and the tree that bears it, always supposing that tree to be the oak. But they choose groves of oaks for the sake of the tree alone, and they never perform any of their rites except in the presence of a branch of it.”
Pliny goes on to describe the ceremony, in which a druid, clad in a white robe, climbs a sacred oak tree and cuts the mistletoe with a golden sickle. The mistletoe falls from the tree and is caught in a white cloth—it’s never allowed to touch the ground. (More on that later.) After the mistletoe is cut from the tree, a prayer is spoken and two white oxen, “whose horns had never been bound,” are slaughtered.
According to Pliny, this all takes place on the “sixth day of the moon,” i.e. during a waxing moon. The prayer and sacrifice are made to a god in exchange for prosperity, but Pliny does not reveal which god, nor does he elaborate on the nature of the prosperity said god bestows upon the ceremony’s participants. Of course, one interpretation is that the mistletoe itself could have been their divine reward.
Known by the ancient Celts as “the universal healer” or “all-healer,” mistletoe was believed to cure all manner of wounds and serve as an antidote to all manner of poisons. What’s more, a potion made from mistletoe was believed to make barren animals “fruitful.”
Among the Rhine-dwelling Teutons (who may actually be Germanic and not Celtic in origin—it’s still up for debate), a glue obtained from mistletoe was “looked upon as a panacea against the sterility of women, the ravages of diseases, the effects of witchcraft, and also as a means to catch birds.” (source: Myths of the Rhine, translated from the French of X. B. Saintine by Prof. M. Schele De Vere, 1874).
But if you’d asked MacCulloch, he’d of told you that there’s got to be more to the Celtic mistletoe rite than what Pliny recorded. As he puts it:
“We can hardly believe that such an elaborate ritual merely led up to the medico-magical use of the mistletoe.”
source: The Religion of the Ancient Celts (1911)
MacCulloch proposes that the ceremony preceded the cutting down of the entire tree, as the tree was likely a representation or embodiment of a god or divine king. He notes that, at the time, gods were often equated with oak trees and daur (“oak”) was an early Irish name for god. Here’s a more in-depth explanation from MacCulloch:
“The Irish bile or sacred tree, connected with the kings, must not be touched by any impious hand, and it was sacrilege to cut it down. Probably before cutting down the tree a branch or something growing upon it, e.g. mistletoe, had to be cut, or the king’s symbolic branch secured before he could be slain. This may explain Pliny’s account of the mistletoe rite. The mistletoe or branch was the soul of the tree, and also contained the life of the divine representative. It must be plucked before the tree could be cut down or the victim slain.”
source: The Religion of the Ancient Celts (1911)
Folklorist and anthropologist James George Frazer elaborates on this concept in his famous work of comparative mythology and religion, The Golden Bough, explaining the reason the mistletoe had to be cut was that it protected its host tree from harm (sort of like one of those invisible suits of armor in Dune—my simile, not Frazer’s).
“The mistletoe was viewed as the seat of life of the oak, and so long as it was uninjured nothing could kill or even wound the oak… Hence when the god had to be killed—when the sacred tree had to be burnt—it was necessary to begin by breaking off the mistletoe. For so long as the mistletoe remained intact, the oak (so people might think) was invulnerable; all the blows of their knives and axes would glance harmless from its surface. But once tear from the oak its sacred heart—the mistletoe—and the tree nodded to its fall. And when in later times the spirit of the oak came to be represented by a living man, it was logically necessary to suppose that, like the tree he personated, he could neither be killed nor wounded so long as the mistletoe remained uninjured. The pulling of the mistletoe was thus at once the signal and the cause of his death.”
source: The Golden Bough (1890)
Pretty fascinating, right? But this really hasn’t gotten us any closer to answering our original question…or has it?
Why Do People Put Up Mistletoe at Christmas?
Let’s tackle the first half of this question first and, in doing so, let’s apply a literal lens. Because it’s actually quite easy to understand why people hang mistletoe, rather than stick it in a vase or centerpiece: As we’ve said before, mistletoe grows on trees, up in the air. ‘Tis not a ground-dwelling plant.
In addition to its evergreen-ness, the airborne-ness (those are words, right?) of the mistletoe likely contributed to its interpretation as a holy plant, a plant imbued with the soul of its host tree. For the mistletoe can be said to hover between heaven and earth. To quote Frazer:
“Primitive man might think that, like himself, the oak-spirit had sought to deposit his life in some safe place, and for this purpose had pitched on the mistletoe, which, being in a sense neither on earth nor in heaven, might be supposed to be fairly out of harm’s way… We can therefore understand why it has been a rule both of ancient and of modern folk-medicine that the mistletoe should not be allowed to touch the ground; were it to touch the ground, its healing virtue would be gone. This may be a survival of the old superstition that the plant in which the life of the sacred tree was concentrated should not be exposed to the risk incurred by contact with the earth.”
source: The Golden Bough (1890)
So, there you have it. People hang mistletoe because folkloric tradition, passed down from generation to generation, has taught them that it is forbidden to let mistletoe touch the ground. It would ruin the magic, as it were. In his 1912 book Christmas In Ritual and Tradition, Christian and Pagan, author and folklorist Clement A. Miles gives an example of how this belief persisted into modern times:
“The sanctity of Christmas house-decorations in England is shown by the care taken in disposing of them when removed from the walls. In Shropshire, old-fashioned people never threw them away, for fear of misfortune, but either burnt them or gave them to the cows; it was very unlucky to let a piece fall to the ground.”
source: Christmas In Ritual and Tradition, Christian and Pagan (1912)
Now, for the second part of the question: Why did mistletoe become a popular Christmastime decoration? There’s also a simple explanation here: Mistletoe was traditionally collected during the solstices, Midsummer and Midwinter. As Frazer explains:
“[T]he mistletoe is gathered either at Midsummer or Christmas—that is, at the summer and winter solstices—and, like fern-seed, it is supposed to possess the power of revealing treasures in the earth.”
source: The Golden Bough (1890)
Did you catch that bit about mistletoe being able to reveal treasures? More on that later.
Now, in addition to the ancient Celts collecting mistletoe during the winter solstice, there’s the symbolism of the aforementioned “evergreen-ness” of mistletoe to consider (i.e. life persisting in the starkness of winter). What’s more, mistletoe doesn’t merely persist in winter, it thrives; it bears fruit, which also may have contributed to why the plant became associated with Midwinter. To quote Miles:
“Some further consideration may now be given to the subject of Christmas decorations in various lands. In winter, when all is brown and dead, the evergreens are manifestations of the abiding life within the plant-world, and they may well have been used as sacramental means of contact with the spirit of growth and fertility, threatened by the powers of blight. Particularly precious would be plants like the holly, the ivy, and the mistletoe, which actually bore fruit in the winter-time.”
source: Christmas In Ritual and Tradition, Christian and Pagan (1912)
Full disclosure: From a decorating perspective, mistletoe hasn’t always been associated strictly with Christmas. In some communities in England, for example, people would wait until New Year’s to bust out the mistletoe. As Miles explains:
“The Shropshire custom was to leave the holly and ivy up until Candlemas, while the mistletoe-bough was carefully preserved until the time came for a new one next year. West Shropshire tradition, by the way, connects the mistletoe with the New Year rather than with Christmas; the bough ought not to be put up until New Year’s Eve.”
source: Christmas In Ritual and Tradition, Christian and Pagan (1912)
Even this tradition is likely to have a Celtic origin, however. For while the Celts were known to gather mistletoe on Midwinter, the Gaulish Celts would gift it to one another on New Year’s. To quote Saintine:
“The Gauls…dried [the mistletoe] carefully and put the dust into pretty little scent-bags, which they presented to each other as New Year’s Gifts on the first day of the year. Hence, in some provinces of France, the cry is still heard, ‘Aguilanneuf’ (au gui l’an neuf), ‘Mistletoe for New Year!'”
Myths of the Rhine (1874)
Why Do People Kiss Beneath the Mistletoe?
To recap, we know that mistletoe was historically associated with fertility. And we know some ancient peoples believed mistletoe could “reveal treasures”. Now, imagine if, down the line, later generations synthesized these two characteristics of mistletoe and came to believe that the plant was capable of divining romantic futures.
Turns out, you don’t have to imagine: this is exactly what happened. Or at least it’s what happened in some corners of Britain. To quote Frazer:
“At Pulverbatch, in Shropshire, it was believed within living memory that the oak-tree blooms on Midsummer Eve and the blossom withers before daylight. A maiden who wishes to know her lot in marriage should spread a white cloth under the tree at night, and in the morning she will find a little dust, which is all that remains of the flower. She should place the pinch of dust under her pillow, and then her future husband will appear to her in her dreams. This fleeting bloom of the oak, if I am right, was probably the mistletoe…The conjecture is confirmed by the observation that in Wales a real sprig of mistletoe gathered on Midsummer Eve is similarly placed under the pillow to induce prophetic dreams.”
source: The Golden Bough (1890)
No, there’s no smooching in the above examples, and there’s no Christmas, but there is a courtship ritual in the making. It reminds me of the origins of bobbing for apples, another courtship ritual that began as an ancient Celtic ceremony. And one can glean from the above passage the evolution of mistletoe from a lucky/holy/healing plant to a plant that is capable of predicting who will fall in love with whom.
Now, imagine you’re a young whippersnapper at a Christmas celebration in 18th-century England, and you see this evergreen plant—with its plump berries and romantic connotations—hanging above your head and the head of your sweetheart. Might you lean in for a kiss? It’s entirely possible that’s how the tradition got started. As Miles explains:
“It is hard to say exactly what is the origin of the English ‘kissing under the mistletoe,’ but the practice would appear to be due to an imagined relation between the love of the sexes and the spirit of fertility embodied in the sacred bough, and it may be a vestige of the licence often permitted at folk-festivals. According to one form of the English custom the young men plucked, each time they kissed a girl, a berry from the bough. When the berries were all picked, the privilege ceased.”
source: Christmas In Ritual and Tradition, Christian and Pagan (1912)
There is another school thought, however, that says kissing under the mistletoe is not British/Celtic in origin, but Norse. Specifically, there’s the story of Baldur, in which his mother Frigga casts a spell to prevent any plant grown on earth from being used against Baldur as a weapon. Loki, cunning as he is, makes a spear out of mistletoe, which—as we’ve learned—grows above the earth.
Long story short: Baldur dies. Frigga is sad, and, in some retellings, she declares mistletoe to be a symbol of love and henceforth kisses anyone who passes beneath it. Seems like a pretty straightforward origin for the custom of kissing beneath the mistletoe at Christmas, right? Only here’s the thing:
It’s bullshit.
As historian Mark Forsyth, author of A Christmas Cornucopia: The Hidden Stories Behind Our Yuletide Traditions, explains: “Baldur’s death involves mistletoe, but it’s got nothing to do with kissing or Christmas.” (source: TIME)
Forsyth goes on to note that the tradition, as we know it today, started in England sometime between 1720 and 1784, with the earliest written reference to it appearing in a song published in 1784:
“What all the men, Jem, John, and Joe,
Cry, ‘What good-luck has sent ye?’
And kiss beneath the mistletoe,
The girl not turn’d of twenty.”
And while there is no definitive explanation as to how the custom of kissing under the mistletoe got started in 18th-century England, Forsyth has an idea:
“I can take a pretty shrewd guess that it involved a particularly lusty and inventive boy, and a particularly gullible girl.”
source: A Christmas Cornucopia: The Hidden Stories Behind Our Yuletide Traditions (2018)
Even if we take this very probable origin story as the truth, it does not rule out the influence Celtic culture had on this kissing ritual. After all, our theoretical “lusty and inventive” English boy would have lived in a society where the mistletoe’s magico-romantic connotations—passed down from ancient Celts—were already present.
If only there were another piece of evidence that could bolster the Celtic-origin-for-kissing-under-the-mistletoe hypothesis. Say, the presence of a similar custom in a region (not in Britain) that would have similarly experienced Celtic influence in its early history. Ladies and gentlemen, I give you… Austria. To quote Miles:
“Kissing under the mistletoe seems to be distinctively English. There is, however, a New Year’s Eve custom in Lower Austria and the Rhaetian Alps that somewhat resembles our mistletoe bough practices. People linger late in the inns, the walls and windows of which are decorated with green pine-twigs. In the centre of the inn-parlour hangs from a roof-beam a wreath of the same greenery, and in a dark corner hides a masked figure known as “Sylvester,” old and ugly, with a flaxen beard and a wreath of mistletoe. If a youth or maiden happens to pass under the pine wreath Sylvester springs out and imprints a rough kiss. When midnight comes he is driven out as the representative of the old year.”
source: Christmas In Ritual and Tradition, Christian and Pagan (1912)
This is easily one of the creepiest customs I’ve ever heard of… which totally aligns with all of the creepy stuff (by today’s standards) that the ancient Celts got up to. It’s also worth noting that Austria is, arguably, the “birthplace” of the Celts, with the earliest traces of Celtic culture appearing in what is now Hallstatt, Austria in the early Iron Age (around 1200 BCE).
Final Thought
It’s incredible to think that a seemingly mundane holiday decoration could have such a rich history, stretching back thousands of years.
If you find yourself beneath the mistletoe this Midwinter, I urge you to ponder the vastness of our shared existence on this planet. Remember the druid in his white robe, shimmying up a tree with his golden sickle. Save a thought for the slain white oxen.
Oh, and if you’re puckering up in anticipation of a big old smooch, make sure to get permission first before you lay it on someone. While kissing under the mistletoe has an ancient origin, we are all modern people living in modern times. Let’s act like it, shall we?
Further Reading
A Christmas Cornucopia: The Hidden Stories Behind Our Yuletide Traditions by Mark Forsyth
The Religion of the Ancient Celts by J. A. MacCulloch
The Fairy-Faith in Celtic Countries by Walter Evans-Wentz
The Golden Bough by James George Frazer
Christmas In Ritual and Tradition, Christian and Pagan by Clement A. Miles
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