OI: "earth spear"

While on the one hand, the figure of Tlachtga is one of the many tragic heroines of Irish myth (such as Deirdu or Grainne), she is also an onomastic device--that is, she is a figure used to explain the name of a geographic location. This location is the Hill of Ward, near Tara.

There are two references to Tlachtga in Irish literature; the first is the banshenchas "the Lore of Women" which sought to act as a sort of condensed guide to the various women of Irish myth. The second source is the dindsenchas "the Lore of Places" which sought to explain the names of various locations in Ireland. In each poem, we are told that Tlachtga is the daughter of Mog Roith, a powerful druid of Munster, and is associated with the son or sons of Simon Magus, often tragically.

Here follow the two versions of her story:

From The Banshenchas

Tlachtga, daugther of fat Mog Ruith was the mighty wife of the son of Simon of the jewels. From her, because of the martyr she slew, is named the hill of the flocks. Midir slew Fuamnach with violence. Her jealousy was cruel to herself and Etain.

From The Metrical Dindsenchas

The prose introduction:

Why was Tlachtga so called? Not difficult. Tlachtga was the daughter of Mog Roith, son of Fergus. Three sons of the magician Simon raped her.

She went with her father to learn the magic arts practised anywhere in the world. And it was she who made for Trian the Rolling Wheel, the stone in Forcathu and the pillar in Cnamchaill1. She came from the East and brought with her these things until she reached the hills of Tlachtga.

It was there she bore three sons, Doirb, Cumma and Muach, who gave their names to three regions. As long as their names are remembered in Ireland the land will not be visited by vengeful strangers.

Tlachtga Hills, splendid and high,
Foreboding doom to a great, unswerving king
Before the step which Tlachtga... took,
The daughter of King Roth's clever votary.
Mog Roith, the son of Fergus Fal,
The kingly and noble son of Ross.

Cacht, the daughter of the quarrelsome Catmend
Was his colourful arid noble mother.
Roth, son of Rigoll was his fosterer.
This is why the name 'Mog Roith' was given him.
Two sons of Mog: Buan and Fer-Corb,
Were successful over armies in deeds of liberation.
She (Cacht) was the (foster) mother of the handsome sons
Of Der-Droighen, dark, strong and active,
And the real mother of Cairpre.
It is certain that he deceived the Hui-Bairdne.2

The daughter of Mog hosted with thousands,
Tlachtga, the chosen--not that she was without feelings
To accompany her great and noble father,
To noble Simon of sevenfold splendour.
Three sons had Simon pleasing to look upon:
Sorrowful her struggle with their devilry.
... {text missing}... powerful.
Theirs was a powerful family, vehement and resilient.
The sons grew passionate
Towards Tlachtga at the same time,
They flowed into her body--it is no lie (making)
Descendants of beauty and lineage.

For Trian it was no honour
Tlachtga created the red and swiftly mobile wheel,
Together with the great and noble Mog,
And with Simon of sevenfold splendour.
She brought with her wise sayings;
She left the moving wheel,
The finished stone of Forcarthu she left,
And the pillar in Cnamchaill.
Whoever sees it will become blind,
Whoever hears it will become deaf,
And anyone who tries to take a piece of the
Rough spoked wheel will die...

After the woman came from the East,
She gave birth to three sons after hard labour.
She died, the light and lively one.
This urgent, unconcealable news was to be heard.
The names of the sons were of great import...
Muach and Cuma and Doirb the noble.
The crowd... {text missing}...
Because it is appropriate that they shall hear it:
That as long as over the stately Banba
The names of the three sons are remembered
As the truthful story tells...
No catastrophe will befall its inhabitants.
The hill where this woman from the East is buried,
To surpass all other women,
This is the name it was given:
The Hill of Tlachtga.

Tlachtga means "earth spear" from tlacht "earth" and gae "spear." The hill is the site of a great oenach--gathering--where the druids would light the bruane Samhna--new year bonfires on Samhain (this was not at Tara). Now called Ward Hill (or Hill of Ward), it lies 12 miles northwest of Tara. Tlachtga was then the point where the druids felt that this world and the otherworld were closest at the new year; this tradition was later blended with that of Tara, which would then be associated with the holy center of Ireland. The hill had consisted of a raised enclosure surrounded by four banks and ditches--a series of rings; these were disturbed in 1641.

The odd thing about the banshenchas version is that Tlachtga's story is rather incongruously combined with that of Etain and Midir. Fuamnach is the spurned wife of Midir. Briefly, Midir has fallen for Etain, and when Fuamnach hears of this, she turns Etain into a butterfly, which then starts the story of the Wooing of Etain. It isn't clear what this has to do with Tlachtga's story. Moreover, the unnamed martyr that Tlachtga is said to have slain may be a confusion with the legend of her father, given below.

Now, Tlachtga is a sun goddess--one of several in Irish mythology (another being Grainne wife of Finn mac Cumhail). However, it is a monkish invention to identify the father of her rapists with the biblical/gnostic Simon Magus. This is derived from an odd medieval Irish tale about the beheading of John the Baptist. In this tale, the executioner is Mog Roith, who then takes up with Simon Magus, and after Simon is discredited, goes off to Ireland with his daughter. However, in the tale "The Siege of Knocklong" (ICK), Mog Roith is a powerful druid of Munster, able to defeat the forces of Cormac mac Airt. This is likely the original tradition. But as we have seen, a third tradition in the banshenchas credits Tlachtga with the killing of a martyr--again, this is likely a confusion with Mog Roith.

The name Mog Roith apparently means "devote of the wheel," and it is assumed that the wheel in question--as well as the wheel that Tlachtga makes--is the sun. This could then mean that the Samhain fires held on her hill were a way of recapturing the sun's light in the new year--a way of ensuring light against the growing darkness of winter. The "pillar" is thought to represent lightning--and this would then explain the name "earth spear", for lightning was a spear thrown at the earth. She is then also not only goddess of the sun, but of lightning and storms.

The theme of a goddess who dies in childbirth, giving her name to the land, is also seen in the story of Macha in the Ulster Cycle. In dying and entering the earth, her power then resides in the land.


The Banshenchas:
"The Banshenchsa Part I" ed. by Margaret E. Dobbs. Revue Celtique vol. xlvii. 1930. Found on the web at

The Dindsenchas:
Matthews, John & Caitlinn. The Encyclopedia of Celtic Wisdom. Rockport, MA.: Element. 1994. Reprints selections of Gwynn's Metrical Dindsenchas (see following):

The Metrical Dindsenchas Volume IV. trans. Edward J. Gwynn. Reprint. Dublin: Dublin Institute for Advanced Studies, School of Celtic Studies. 1991.


2. Cnamchaill: "bone damage"

3. Hui-Bairdne: "descendents of the bards"?