The Mythology of Samhain: 6 Stories That Give Samhain Added Significance

image created with Craiyon using the prompt "samhain mythology"

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If you’ve been following along with my Samhain series, you already know the deal: Samhain is the Celtic New Year, marking the end of summer and the last harvest before winter. It was a time, as I’ve mentioned ad nauseam, when the barrier between our world and the world of the dead was thought to grow thin, allowing spirits to cross over.

“These supernatural spirits ruled the dead,” according to author and librarian Ruth Edna Kelley (source: The Book of Hallowe’en, 1919). But there’s more to the story than that. Because it turns out these so-called “spirits” are deeply rooted in Irish mythology.

As Kelley explains:

“There were two classes [of spirits]: the Tuatha De Danann, ‘the people of the goddess Danu,’ gods of light and life; and spirits of darkness and evil.”

source: The Book of Hallowe’en (1919)

What Kelley is alluding to here is the folklorization of two mythical Irish races: the gods of Irish mythology—the Tuatha Dé Danann—who were ultimately driven underground to their mounds, or sídhe, where they became known as the aes sídhe, or fairies; and the “bad guys” of Irish mythology—the Fomorians (a.k.a. Fomori)—the monstrous, semi-aquatic arch nemeses of the Tuatha Dé Danann led by Balor of the Evil Eye.

As you’re about to discover, many of Irish mythology’s greatest stories involve either one or both of these pantheons. And as you’ll also see, many of the most significant events involving the Tuatha Dé Danann and the Fomorians took place on Samhain.

1. The Tax

The Fomorians, John Duncan’s interpretation of the sea gods of Irish mythology (1912)

If Samhain wasn’t spooky enough already, with all the ghosts and demons and fairies and ghost-demon-fairies (like the banshee) hovering around… it was also tax day.


Granted, this was back in the era of Fomorian rule, well before the Tuatha De Dannan (gods) or Milesians (Celts) arrived in Ireland. Ireland’s inhabitants at the time were the Nemedians, who themselves had invaded the island, displacing a previous group (the Partholonians).

It’s a whole thing.

By which I mean the subsequent invasions of Ireland—six in total by six different groups: the Cessair, the Partholónians, the Nemedians, the Fir Bolg, the Tuatha Dé Danann, and the Milesians—is a central narrative in Ireland’s mythology, as detailed in the 11th-century Lebor Gabála Érenn, or Book of Invasions (a.k.a. The Book of the Taking of Ireland).

But I digress.

The Fomorians were raiders. Operating out of their fortress on Tory Island (off of County Donegal’s northwest coast), they never settled in Ireland, but preferred instead to make life miserable for its inhabitants—whoever they happened to be at the time.

After decimating the Nemedians, the Fomorians imposed a tax. A gruesome tax. 

Due on Samhain. 

To quote Kelley:

[T]he Fomor, sea-demons, after destroying nearly all their enemies by plagues, exacted from those remaining, as tribute, ‘a third part of their corn, a third part of their milk, and a third part of their children.’ This tax was paid on Samhain. It was on the week before Samhain that the Fomor landed upon Ireland. On the eve of Samhain the gods met them in the second battle of Moytura, and they were driven back into the ocean.”

source: The Book of Hallowe’en (1919)

No, not good. Not good at all. 

But somehow, in another interpretation of this Samhain myth, the tax is even worse. Two times worse, to be precise.

To quote Scottish scholar and folklore researcher J.A. MacCulloch:

From Tory Island the Fomorians ruled Ireland, and forced the Nemedians to pay them annually on the eve of Samhain (Nov. 1st) two-thirds of their corn and milk and of the children born during the year. If the Fomorians are gods of darkness, or, preferably, aboriginal deities, the tribute must be explained as a dim memory of sacrifice offered at the beginning of winter when the powers of darkness and blight are in the ascendant.

source: The Religion of the Ancient Celts (1911)

According to MacCulloch’s analysis, the Fomorians were effectively the original Samhain demons. They were embodiments or manifestations of the darkness and death (especially crop death) associated with the coming winter. 

Appeasing sea-demon deities of darkness required sacrifice, no doubt—perhaps at one time even human sacrifice. And later, that evolved into making offerings of food.

It could be argued that the Fomorians invented the Halloween tradition of trick-or-treating as they forced households to put out snacks. No, seriously. And, in response to the other part of the tax, maybe Nemedian parents dressed up their children in costumes on Samhain eve and sent them out so the Fomorians couldn’t find them? Totally fits.

Am I reaching?

Of course.

But still.

2. The Arrangement

Ambassadors of the Fir Bolg and Tuath Dé meeting before the Battle of Moytura. An illustration by Stephen Reid in T. W. Rolleston's Myths & Legends of the Celtic Race, 1911
Ambassadors of the Fir Bolg and Tuath Dé meeting before the Battle of Moytura. An illustration by Stephen Reid in T. W. Rolleston’s Myths & Legends of the Celtic Race, 1911

Flash forward a couple of invasions and the Tuatha Dé Danann have defeated the Fir Bolg in the first Battle of Magh Tuireadh (a.k.a. the first Battle of Moytura).

The Dagda, the father of the Irish gods, also known as Eochaid Ollathair (the All-Father), is taking a well-deserved break from swinging his magical club, the Lorg Mór (“Great Staff”), which is so huge it has to be wheeled from place to place when not in use.

But even in his down-time, the Dagda is doing whatever it takes to ward off evil—even if that means bumping uglies with the most sinister member of the Tuatha Dé Danann: the Morrígan.

A quick reminder: the Tuatha Dé Danann is named for the Celtic mother goddess Danu, bringer and nurturer of life. As mentioned in my article “What Is Samhain?”, the battle and death goddess the Morrígan is Danu’s divine opposite, possessing “the power of destruction and the fury of slaughter.”

That’s according to archaeologist and academic Barry Cunliffe, who goes on to note that the “ferocious” Morrígan “could bring devastation and death” and “needed careful handling and much propitiation,” (source: Druids: A Very Short Introduction, 2010).

Thus, to keep the Morrígan at bay, the following arrangement was struck:

“The Dagda engaged in intercourse with the Morrígan once a year on the feast of Samain, thus commanding her protection for his people for the year to come.”

source: Druids: A Very Short Introduction (2010)

This is a recurring theme I see in Samhain folklore and mythology: it’s a time when evil hasn’t broken through…not quite yet…or at least not completely. But it’s pushing up against that veil, that thinnest of membranes between worlds. 

So there’s a lingering fear: will this be the year this whole delicate system collapses and evil is unleashed en force?

3. The Arrival

An altar depicting a three-faced god identified as Lugh/Lugus
An altar depicting a three-faced god identified as Lugh/Lugus

A young god walks into the court at Tara—seat of Ireland’s High King—boasting of his many talents. What he does next will lead to one of Irish mythology’s most famous battles.

This is the story of the “Coming of Lugh”, Lugh being an Irish sun-god, cognate with the Gaulish Lugos and the Welsh Lleu.

In Irish mythology, he is the son of Cian, who in turn is the son of Dian Cécht, Irish god of healing and medicine. More infamously, Lugh is also the son of Ethlinn, daughter of Balor of the Evil Eye—leader of the Fomorians.

Fortunately for then-king Nuada of the Silver Hand, Lugh would ultimately decide to join the side of the Tuatha Dé Danann in the battle against the Fomorians. But first, Lugh had to convince the guards to let him into Tara. So he listed off all of his many skills, which included carpentry, blacksmithing, fighting, harp-playing, poetry, storytelling, magic, healing, cup-bearing, and metalworking.

Irish god Lugh and Welsh god Lleu are both descended from the Celtic god Lugus

But with each skill Lugh listed, the guards shook their heads. “We already have someone who can do that,” they told him (paraphrasing).

Finally, Lugh responded: “Go and ask the king if he has any one man that can do all these things, and if he has, I will not ask to come into Teamhair [Tara],” (source: Gods and Fighting Men, 1902).

Lugh was let into Tara, where his claims were promptly put to the test. He completed all of the feats of strength and wit and musical ability leveled at him with flying colors.

I’ll let Irish dramatist and folklorist Lady Gregory tell the rest:

And when Nuada saw all the things Lugh could do, he began to think that by his help the country might get free of the taxes and the tyranny put on it by the Fomor. And it is what he did, he came down from his throne, and he put Lugh on it in his place, for the length of thirteen days, the way they might all listen to the advice he would give.

source: Gods and Fighting Men (1902)

Oh, right, and what was the date of Lugh’s arrival in Tara? You guessed it:


For the next several years, Lugh would help the Tuatha Dé Danann prepare for a battle which would take place on another fateful Samhain. But the Samhain date has another significance as well:

Remember the aforementioned arrangement between the Dagda and the Morrígan? Well, Lugh’s arrival had the potential to jeopardize it, as Lugh was not just some new god—he represented a divine paradigm shift.

To quote Cunliffe: 

There is, however, another male deity – Lug – who at first sight seems to stand aside as something different. He is the antithesis of the Dagda – young, beautiful, and pure, contrasting with the aged, ugly, grossness of the Dagda. His weapons are throwing weapons – the sling and the spear – very different to the Dagda’s heavy club, and whereas the Dagda commands all knowledge, Lug is the many-skilled. One way to structure this would be to see the Lug/Dagda dichotomy as the two opposing sides of a single male deity, much as the Morrígan encompasses the oppositions of wellbeing and destruction contained within the female form. In the overarching scheme, then, the productive and destructive forces of nature confront the traditional and progressive forces in humanity.

source: Druids: A Very Short Introduction (2010)

4. The Battle

flaming spear flying through battlefield
Lugh’s bloodthirsty magical spear described in Charles Squire’s popular book Celtic Myth And Legend, Poetry And Romance, originally published under the title The Mythology of the British Islands (1905)

On Samhain, twenty-seven years after overthrowing the Fir Bolg in the first battle of Magh Tuireadh, the Tuatha Dé Danann, weapons in hand (or, in the Dagda’s case, in tow), returned to the hallowed ground of Magh Tuireadh (a.k.a. Moytura) to confront the Fomorians. 

Or rather, they returned to a spot about 50 miles from the site of the original battlefield (in County Mayo) to a plain in County Sligo.

But let’s not get too bogged down by the details.

The second battle of Magh Tuireadh (a.k.a. Cath Tánaiste Maige Tuired) could, in modern terms, be described as a Tolkien-esque affair, complete with magical weaponry, enchanted armor, battle companions with cool names, horses with even cooler names, and heroes on horseback making dramatic entrances with their armies behind them. No one’s entrance being so dramatic, of course, as you-know-whose…

Nuada was holding a great assembly … they saw an armed troop coming towards them from the east, over the plain; and there was a young man in front of the troop, in command over the rest, and the brightness of his face was like the setting sun, so that they were not able to look at him because of its brightness.

And when he came nearer they knew it was Lugh Lamh-Fada, of the Long Hand, that had come back to them, and along with him were the Riders of the Sidhe from the Land of Promise, and his own foster-brothers, the sons of Manannan, Sgoith Gleigeil, the White Flower, and Goitne Gorm-Shuileach, the Blue-eyed Spear, and Sine Sindearg, of the Red Ring, and Donall Donn-Ruadh, of the Red-brown Hair.

And it is the way Lugh was, he had Manannan’s horse, the Aonbharr, of the One Mane, under him, that was as swift as the naked cold wind of spring, and the sea was the same as dry land to her, and the rider was never killed off her back. And he had Manannan’s breast-plate on him, that kept whoever was wearing it from wounds, and a helmet on his head with two beautiful precious stones set in the front of it and one at the back, and when he took it off, his forehead was like the sun on a dry summer day. And he had Manannan’s sword, the Freagarthach, the Answerer, at his side, and no one that was wounded by it would ever get away alive; and when that sword was bared in a battle, no man that saw it coming against him had any more strength than a woman in child-birth.

And the troop came to where the King of Ireland was with the Tuatha de Danaan, and they welcomed one another.”

source: Gods and Fighting Men (1902)


That’s how you introduce the hero. (Minus that “woman in child-birth” comment, of course.)

Lugh was the undisputed hero of the second battle of Magh Tuireadh, killing his own grandfather—Fomorian leader, Balor of the Evil Eye—with a special slingshot projectile called the Tathlum, made by mixing the blood of toads, bears, and vipers with sea-sand and letting it harden.


Unfortunately, Lugh was not able to deliver this fatal shot until after Balor had slayed Nuada of the Silver Hand, leader of the Tuatha Dé Danann. Thus, while the forces of goodness and light ultimately triumphed over the forces of evil and darkness—on Samhain, no less—it was a bittersweet victory. To quote MacCulloch: 

Samhain may thus be regarded as, in origin, an old pastoral and agricultural festival, which in time came to be looked upon as affording assistance to the powers of growth in their conflict with the powers of blight. Perhaps some myth describing this combat may lurk behind the story of the battle of Mag-tured fought on Samhain between the Tuatha Dé Danann and the Fomorians. While the powers of blight are triumphant in winter, the Tuatha Déa are represented as the victors, though they suffer loss and death. Perhaps this enshrines the belief in the continual triumph of life and growth over blight and decay, or it may arise from the fact that Samhain was both a time of rejoicing for the ingathered harvest, and of wailing for the coming supremacy of winter and the reign of the powers of blight.

source: The Religion of the Ancient Celts (1911)

And MacCulloch isn’t the only scholar to have drawn a connection between Samhain and the second battle of Magh Tuireadh. To quote Kelley:

Samhain was then a day sacred to the death of the sun, on which had been paid a sacrifice of death to evil powers. Though overcome at Moytura, evil was ascendant at Samhain. Methods of finding out the will of spirits and the future naturally worked better then, charms and invocations had more power, for the spirits were near to help, if care was taken not to anger them, and due honors paid.

source: The Book of Hallowe’en (1919)

5. The Raid

Events from the Táin in a mosaic mural in Dublin by Desmond Kinney
Events from the Táin in a mosaic mural in Dublin by Desmond Kinney

So far we’ve been dealing with Samhain myths only from the Mythological Cycle of Irish mythology—the earliest of the four cycles. Now it is time to delve into the second cycle: the Ulster Cycle, also known as the Red Branch Cycle, whose stories concern the battles and skirmishes of the Red Branch warriors, foremost among them Cú Chulainn: the hound of Cullan (a.k.a. the hound of Ulster, a.k.a. the Irish Achilles).

Arguably, Cú Chulainn is Ireland’s greatest hero. Like, of all time. Ever. Even greater than the aforementioned Lugh, who, I should add, is Cú Chulainn’s biological father.

chart showing CuChulainn's family tree

The story that really solidifies Cú Chulainn’s place amongst the greats is the Tain Bo Cualigne (Cattle Raid of Cooley), an epic poem that sees Queen Medb (a.k.a. Maeve) of Connacht attempting to capture a prize bull of Ulster. Specifically, Donn Cuailnge: “The Brown Bull of Cooley”.

See, Donn Cuailnge’s brother, Finnbhennach (“The White-Horned”) once belonged to Queen Medb’s herd. But Finnbhennach was a chauvinist and considered being part of a woman’s herd beneath him (ouch). So, he joined her husband’s cattle herd (twist!). Medb’s plan to capture Finnbhennach’s brother—Ulster’s prized bull, the Brown Bull of Cooley—is born shortly thereafter.

Finnbhennach (left) and Donn Cuailnge (right) - mosaic mural in Dublin by Desmond Kinney
Finnbhennach (left) and Donn Cuailnge (right) – mosaic mural in Dublin by Desmond Kinney

When does Medb launch her attack? 

Ding, ding, ding.


And you better believe that some witchy stuff is a-brewing.

For starters, when Medb’s army arrives in Ulster, all of the Red Branch knights—Ulster’s champions and defenders—are incapacitated with labor pains, courtesy of a curse. In most tellings this curse is conjured by Macha, who is likely an incarnation of the Morrígan.

Macha Curses the Men of Ulster (1904) by Eleanor Hull, The Boys' Cuchulain (Stephen Reid)
Macha Curses the Men of Ulster (1904) by Eleanor Hull, The Boys’ Cuchulain (Stephen Reid)

So it is up to the lad Cú Chulainn—only a teenager at the time—to fight off Medb’s army single-handedly…

Which he does, invoking the right of single combat so he can battle each of Connacht’s champions one-on-one.

It isn’t easy. And the Morrígan, who is constantly shapeshifting and messing with Cú Chulainn during his fights (e.g. by turning into a beautiful woman and seducing him, by turning into an eel and biting him, etc.), doesn’t make it any easier. 

While Maeve’s decision to launch her raid on Samhain probably had more to do with strategic considerations than supernatural ones (as most cattle-raids, a common occurrence in ancient Ireland, took place in the summer), the Samhain date meant that “charms and invocations had more power,” as Kelley told us in the previous section. Thus, Macha/the Morrígan were perhaps able to wield more power than usual—to the detriment of the Red Branch and Cú Chulainn.

Also, it should be noted that while Cú Chulainn took the opportunity of the raid to prove himself as a warrior, Medb still managed to steal Ulster’s prize bull. 

It’s a bittersweet, cursed-with-labor-pains symphony. That’s Samhain.

6. The Showdown

Fionn fighting Otherworld creature with magic spear
Fionn fighting Aillen, illustration by Beatrice Elvery in Violet Russell’s Heroes of the Dawn (1914)

Take all the elements of a good Samhain myth (or any Celtic myth, really)—an otherworldly foe; the testing of a young champion; a magical weapon; FIRE—put them together and you’ve got something approaching the story of Fionn mac Cumhail and the fire-breathing monster Aillén mac Midgna.

Fionn mac Cumhail (a.k.a. Finn McCool), a lad of just ten years—yes, you read that right, he was ten—goes marching into the court at Tara, much in the vein of Lugh, to help the high king with a problem:

For the past twenty years and change, Aillén has crossed over from the Otherworld on Samhain and burnt Tara to the ground with his fire-breath.

However, Fionn is about to put this streak to an end.

This story is from the Fenian Cycle of Irish mythology, FYI, which is third chronologically (after the Ulster Cycle, before the Cycle of Kings). It was originally recorded in the medieval narrative The Boyhood Deeds of Fionn, or Macgnímartha Finn.

Now, on with the show.

Aillén’s secret weapon, apart from his fire-breath, is his timpán (a lyre-like stringed instrument). He is a master of the suantraí (lullaby) style of ancient Irish music, which he deploys, every Samhain, to put the denizens of Tara into a deep, death-like sleep.

Fionn has a solution: the Spear of Fiacha, a.k.a. Birgha (the Spit-Spear), an enchanted, venomous spear which was gifted to him by Fiacha, a member of the Fianna who once served under Fionn’s father, Cumal.

Irish hero Fionn with sword
“Finn Mccool Comes to Aid the Fianna” – Fionn mac Cumhaill meets his father’s old retainers in the forests of Connacht; illustration by Stephen Reid, from The High Deeds of Finn and Other Bardic Fictions of Ancient Ireland.

Fiacha gives Fionn the spear with the express intention that Fionn will slay Aillén on Samhain, saving the royal residence of Tara from destruction. In one version of the story he even teaches Fionn how to use the spear. In another version, it is Fionn who figures out how to unlock the spear’s power. Regardless, the outcome is the same.

During his Samhain battle with Aillén, Fionn presses the spear’s blade to his own forehead and inhales its magical fumes, inoculating himself against Aillén’s timpán music. Our hero is then able to slay the monster.

Fionn gives the spoils of his victory, Aillén’s timpán—or in other versions, Aillén’s severed head—to the High King of Ireland.

The head-gift was par for the course for the ancient Celts, who regularly kept the heads of their vanquished enemies as trophies. But this act may be seen as having even greater significance on Samhain, when the Celtic “cult of the head” was celebrated with carved turnip jack-o’-lanterns

Now, is there any more hidden symbolism or spirituality we can attribute to this story of a boy vanquishing evil on Samhain?

One can’t help but to consider that in some interpretations of Fionn’s lineage, his maternal great-grandfather is Nuada of the Silver Hand, while his maternal great-grandmother is Ethlinn, daughter of Balor of the Evil Eye.

chart showing the family tree of Irish warrior fionn mac cumhail

Which means yes, Fionn is both a descendant of the Tuatha Dé Danann and the Fomorians. A mix of good and evil.

On Samhain, he makes a choice to fight on the side of goodness, holding evil at bay.

Want to learn the rest of the Samhain story? Check out…

Samhain in Your Pocket (Celtic Pocket Guides 2)

Perhaps the most important holiday on the ancient Celtic calendar, Samhain marks the end of summer and the beginning of a new pastoral year. It is a liminal time—a time when the forces of light and darkness, warmth and cold, growth and blight, are in conflict. A time when the barrier between the land of the living and the land of the dead is at its thinnest. A time when all manner of spirits and demons are wont to cross over from the Celtic Otherworld. Learn more…

More the listenin’ type?

I recommend the audiobook Celtic Mythology: Tales of Gods, Goddesses, and Heroes by Philip Freeman (narrated by Gerard Doyle). Use my link to get 3 free months of Audible Premium Plus and you can listen to the full 7.5-hour audiobook for free.

4 thoughts on “The Mythology of Samhain: 6 Stories That Give Samhain Added Significance

  1. Awesome article!

    I was hoping you’d be able to clear something up for me, please?

    I’ve seen it written a few times where the Fomorians and the Fir Bolg are interchangeable in the name. Are they the same race or are they distinctly different races?

    Liked by 1 person

    1. Thanks for the question! This is something I’ve been confused about before too. According to the Book of Invasions (Lebor Gabála Érenn), the Fomorians and the Fir Bolg (“Bag Men”) are two distinct groups. Both were enemies of the Tuatha Dé Danann at certain points, which I think is what leads to some modern writers conflating them / mixing up which group was part of which battle (for the record: the First Battle of Magh Tuireadh = Fir Bolg vs. Tuatha Dé Danann; the Second Battle = Fomorians vs. Tuatha Dé Danann. One of the key differences between the two groups is that the Fir Bolg settled in Ireland (with the Tuatha Dé Danann ultimately displacing them), whereas the Fomorians raided and extracted taxes from the island but never settled there.

      Liked by 1 person

      1. Not a problem and thanks for the reply!

        The mixing of the two by later writers makes sense, especially if they start thinking them as different terms for the same people….. when in fact, they aren’t! But both battles take part in the same place perhaps creating the confusion!

        Thank you for the explanation: Fir Bolg at the first battle, Fomorians at the second. And thank you for explaining the Fomorians were sea-based rather than settled on the land.

        Cheers! 🍺

        Liked by 1 person

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