The Language of the Otherworld: What the Fairy Tongue Tells Us About Ancient Wales

Written by Simon Williams

The Welsh fairy tradition preserved the only recorded fragment of an Otherworld language: words spoken by the Tylwyth Teg, noted by Gerald of Wales in 1191 from the account of a boy named Elidurus who spent a year living among them underground.

Key Facts

• Primary source: Gerald of Wales, Itinerarium Cambriae (c.1191)
• Key figure: Elidurus, a twelfth-century Welsh boy who entered the fairy world aged twelve
• Fairy language sample: Udor udorum (water) and Halgein udorum (salt)
• Linguistic character: Consistent grammatical suffix (udorum) suggesting a genuine if fragmentary system rather than random sounds
• Welsh interpretation: The fairy language as the tongue of the original inhabitants of the land, preserved in the Otherworld while surface languages changed
• Gerald's conclusion: The language sounded like a corrupted form of Greek or Irish because it was genuinely ancient

Language is identity. Every community that has ever faced the erosion or loss of its mother tongue knows this truth in the most visceral possible way.

Wales knows it better than most.

The Welsh language is one of the oldest living languages in Europe. It has survived Roman occupation, Anglo-Saxon expansion, Norman conquest, and centuries of English political dominance that at various points made the active use of Welsh a disadvantage, a mark of cultural inferiority, and in some institutional contexts a punishable offence. The survival of Welsh as a living language is one of the most remarkable stories of cultural resilience in European history.

Against this background, the Welsh belief that the Tylwyth Teg had their own separate and ancient tongue takes on a significance that goes far beyond the merely folkloric. The fairy language was not just a supernatural curiosity. It was a statement about time, about ancestry, and about the layers of memory that the Welsh landscape contained.

I explore the full world of Welsh fairy belief in my book Welsh Myths and Legends: Fairies, Hounds and Holy Wells, available on Amazon. But let us begin with the most remarkable piece of evidence we have for the fairy language: the account of a boy named Elidurus.

The Account of Elidurus: A Boy in the Otherworld

The story of Elidurus is one of the most extraordinary accounts in the entire body of Welsh fairy literature, not least because it comes to us through a relatively reliable medieval source: Gerald of Wales, the twelfth-century writer and cleric who recorded the story in his Itinerarium Cambriae, the Journey Through Wales, written around 1191.

Gerald was not a man who accepted supernatural claims uncritically. He was educated, travelled, and intellectually sophisticated by the standards of his age. He records the story of Elidurus as something told to him directly by the Bishop of St David's, who had heard it from the priest Elidurus himself in his old age.

The story, as Gerald tells it, runs as follows.

Elidurus was a boy of twelve who, after a harsh punishment from his teachers, ran away from his school and hid in a hollow riverbank. After two days without food, two small men of pygmy stature appeared and offered to lead him to a land of games and pleasure. He followed them through an underground passage into a world of perpetual twilight: not dark, but never fully lit, as though the sun was always just below the horizon.

The land he entered was beautiful. The people who inhabited it were small and fair-haired, riding horses the size of greyhounds. They did not eat meat or fish. They had no religious beliefs of any kind that Elidurus could identify. They played constantly with golden balls. And their king took a liking to the boy and gave him a companion of his own age.

Elidurus spent a year in this world, returning regularly to the surface to visit his mother. On one of these visits, his mother asked him to bring her a golden ball from the fairy world. He took one. When he fled back toward the surface with it, the small men who had been his companions gave chase. He stumbled at the threshold between worlds and the ball fell from his hands. The small men seized it and withdrew, and Elidurus was never able to find the entrance to the underground world again.

He spent the rest of his life trying.

The Words That Survived

The part of Elidurus's account that interests me most, and that I believe has been significantly underappreciated in the scholarship on Welsh fairy belief, is the fragment of fairy language that Gerald of Wales preserved.

The fairy beings, when they spoke among themselves, used a language quite unlike Welsh. When they asked for water, they said Udor udorum. When they asked for salt, they said Halgein udorum.

Gerald, who was a man of considerable classical learning, examined these words and concluded that they sounded like a corrupted form of Greek or Irish. Udor does bear some resemblance to the Greek word for water, hudor, and halgein has been compared to various Celtic roots for salt. But no convincing derivation from any known language has ever been established.

What strikes me about these words is not their etymology but their structure. They have a grammar. Udorum appears as a suffix in both examples, suggesting a consistent grammatical pattern rather than random syllables. This is not the invented gibberish of a storyteller trying to sound mysterious. It has the character of a genuine, if fragmentary, linguistic sample.

Gerald's own conclusion was that the language sounded like Greek or Irish because it was genuinely ancient, a relic of a very early form of language that had been preserved in isolation from the developments that had transformed both Welsh and the other languages of Britain.

The Welsh understanding went further than Gerald's scholarly analysis.

The Deep Memory Theory: Fairies as the Ancient Ones

To the Welsh communities that told and retold the story of Elidurus, the fairy language was not merely an interesting puzzle. It was a confirmation of something they already understood about who the Tylwyth Teg were.

The Welsh did not primarily conceive of the fairy beings as alien creatures from another dimension, utterly separate from human history and human ancestry. They understood them, in many traditions, as the descendants of the original inhabitants of the land, the people who had been there before the Welsh, before the Romans, before anyone whose history was recoverable through ordinary means.

This is a profound and sophisticated idea. It suggests that the Welsh understood their landscape as layered with human history in ways that went deeper than any written record could reach. The hollow hills and the ancient mounds were not merely interesting geological formations. They were the remnants of a previous civilisation, one that had been pushed to the margins of the visible world by the arrival of later peoples, but that had never entirely disappeared.

The Tylwyth Teg, on this reading, were not supernatural beings at all. They were the survivors of that earlier world, living in its hidden spaces, speaking its ancient language, maintaining its ancient customs, and occasionally crossing the threshold into the human world that had superseded theirs.

The fairy language was the language of the deep past. And the fact that it sounded like no known tongue was not because it was supernatural, but because it was simply older than any living memory could reach.

Language, Identity, and the Margins of the World

This understanding of the fairy language connects to something I find genuinely moving about the Welsh relationship with their own cultural identity.

Wales has spent much of its recorded history as a culture under pressure, a culture that has had to fight, repeatedly and at considerable cost, to maintain its distinctiveness against the absorption that political power and demographic change have consistently threatened. The Welsh language has been the primary site of that struggle, the thing that, more than anything else, has marked the boundary between Welsh identity and the English identity that surrounds it.

In this context, the belief that the land itself harboured an even older language, spoken by beings who had been there before the Welsh and who had retreated to the hollow hills rather than abandon their tongue, is not merely picturesque. It is a statement about the relationship between language, place, and identity that runs very deep in Welsh culture.

The Tylwyth Teg kept their language. They did not give it up when the world changed around them. They did not assimilate or accommodate or find a pragmatic accommodation with the languages of those who came after them. They withdrew, and they kept speaking.

For a culture that has always understood the keeping of language as an act of identity and resistance, the fairy beings who refused to abandon their ancient tongue were not merely interesting folklore. They were a model.

Other Glimpses of the Otherworld's Speech

The account of Elidurus is the most detailed record of the fairy language in the Welsh tradition, but it is not the only one.

The broader Welsh fairy tradition consistently described the language of the Tylwyth Teg as a noisy, jabbering sound to the untrained ear, rapid and rhythmic and impossible to follow for someone who had not grown up with it. This description is interesting because it suggests that the fairy language was not simply random sounds but a genuine system with its own patterns and rhythms, one that could be learned, at least in principle, by those who spent enough time among its speakers.

Elidurus clearly acquired some facility in it during his year in the Otherworld. He was able to communicate with his fairy companion and to participate in the life of the fairy community. The fact that he retained fragments of the language in his old age, fragments precise enough for Gerald of Wales to record them, suggests that whatever he had learned in the Otherworld was genuinely memorable as a linguistic system rather than simply as sound.

The Mabinogion offers occasional glimpses of the boundary between Welsh and the Otherworld's communication, though these are usually expressed through the medium of magic and transformation rather than explicit linguistic difference. The great figures of the Mabinogion, Gwyn ap Nudd, Rhiannon, the lake maidens, all communicate effortlessly in Welsh when they choose to engage with the human world. The fairy language was a private tongue, used within the Otherworld community, not a barrier to communication with humans but a marker of a distinct identity that human contact did not erase.

The Fairy Language and Welsh Linguistic Consciousness

I want to make one more observation before we conclude, because I think it is the most important one.

The Welsh tradition of fairy language is, among other things, an expression of a culture's consciousness of its own linguistic history. The Welsh knew, because they lived it, that languages change over time, that words and grammatical structures that were current in one generation become archaic in the next, and that the deep past speaks in a tongue that the present can no longer fully understand.

The fairy language, in this light, is the Welsh imagination's version of what lies at the bottom of linguistic time: the original speech, the tongue of the first people, preserved in the hollow hills by beings who had no reason and no desire to change.

This is not a primitive idea. It is a sophisticated one, and it connects Welsh fairy belief to some of the most interesting questions in the study of language, memory, and cultural identity.

The Cyfarwyddiaid who preserved and transmitted the story of Elidurus and the fragments of fairy speech were not just entertainers. They were, in their own way, linguists and archaeologists of the deep past, keeping alive the community's sense that the land it inhabited was layered with histories that went deeper than any written record could reach.

That sense of depth, of a landscape that contains more than it shows, is one of the things I find most distinctive and most compelling about Welsh mythology. And the language of the Otherworld is one of its most extraordinary expressions.

The fairy tongue is one thread in a much larger tapestry. For the full tradition, from the Tylwyth Teg who spoke it to the Otherworld they inhabited, our guide to Welsh mythology covers the complete landscape of Welsh supernatural belief.

This article is part of the Myths and Legends series. Read all articles at historiesandcastles.com/blogs/myths-and-legends.

Deepen Your Understanding

→ Who Are the Tylwyth Teg?: The Fair Family whose language Elidurus learned — the complete guide to their mythology, their relationship to the Otherworld, and what Welsh tradition believed about their origins

→ Gwyn ap Nudd and the Welsh Otherworld: The lord of Annwn and the Otherworld that Elidurus entered — the full tradition of what Welsh mythology believed lay beneath the hollow hills

→ Rhiannon, Arianrhod, and Blodeuwedd: The great figures of Welsh mythology who crossed the boundary between the Otherworld and the human world, communicating in Welsh while carrying their Otherworld identity

→ The Mabinogion Decoded: The mythological cycle in which the boundary between Welsh and Otherworld communication is explored through transformation and magic rather than explicit linguistic difference

→ The Cyfarwyddiaid: Wales's Professional Storytellers: The tradition-bearers who preserved the account of Elidurus and the fragments of fairy speech across the centuries until Gerald of Wales recorded them

→ Welsh Mythology: The Complete Beginner's Guide: The full landscape of Welsh supernatural belief within which the fairy language tradition sits

People Also Ask

Who was Elidurus and what happened to him?

Elidurus was a Welsh boy of twelve who, according to Gerald of Wales writing c.1191, fled his school after a harsh punishment and hid in a hollow riverbank for two days. Two small men of pygmy stature appeared and led him through an underground passage into a world of perpetual twilight inhabited by small, fair-haired people who rode horses the size of greyhounds. He spent a year there, returning regularly to the surface to visit his mother, until he attempted to steal a golden ball from the fairy world on her request. He fled, stumbled, lost the ball, and was never able to find the entrance to the underground world again. He spent the rest of his life searching.

What fairy language words did Gerald of Wales record?

Gerald of Wales recorded two words from the fairy language as told to him by the Bishop of St David's, who had heard them directly from the priest Elidurus in his old age. When the fairy beings asked for water, they said Udor udorum. When they asked for salt, they said Halgein udorum. Gerald noted that these words sounded to him like a corrupted form of Greek or Irish. The word udor bears some resemblance to the Greek word for water (hudor), and halgein has been compared to Celtic roots for salt, but no convincing derivation from any known language has been established.

What did Welsh tradition say about where the fairy language came from?

Welsh tradition did not primarily understand the fairy language as an alien tongue from another dimension. Instead, many traditions identified the Tylwyth Teg as descendants of the original inhabitants of the land: people who had been there before the Welsh, before the Romans, before anyone whose history was recoverable through ordinary means. On this reading, the fairy language was the language of the deep past, the tongue of the first people of Britain, preserved in isolation in the hollow hills while the surface languages changed beyond recognition. The fact that it sounded like no known tongue was not because it was supernatural but because it was simply older than any living memory could reach.

What does "Udor udorum" mean?

Gerald of Wales recorded Udor udorum as the fairy phrase for water, and Halgein udorum as the fairy phrase for salt. The precise meaning of the words in any known language has never been established, but Gerald observed that they resembled corrupted Greek or Irish. The word udor is comparable to the Greek hudor (water), and the consistent use of udorum as a suffix in both phrases suggests a grammatical pattern rather than random syllables. Gerald's scholarly conclusion was that the consistency indicated genuine linguistic structure, and that the resemblance to Greek and Irish indicated extreme antiquity rather than supernatural origin.

How did Gerald of Wales interpret the fairy language?

Gerald of Wales, writing in his Itinerarium Cambriae c.1191, was not a credulous recorder. He was educated, widely travelled, and intellectually sophisticated by the standards of his age. He recorded the story of Elidurus and the fairy language words as information provided by the Bishop of St David's, who had heard them directly from the priest Elidurus in his old age. Gerald examined the words with genuine scholarly attention, comparing them to Greek and Irish, noting their grammatical consistency, and concluding that the most plausible explanation was that they represented a very ancient language preserved in isolation from the developments that had transformed all the known languages of Britain.

What connection does the fairy language belief have to Welsh cultural identity?

The Welsh belief in a fairy language connects to a deep pattern in Welsh culture: the understanding that language, place, and identity are inseparable. Wales has spent much of its recorded history under pressure to abandon or diminish the Welsh language, and the survival of Welsh as a living language is one of European history's most remarkable stories of cultural resilience. In this context, the fairy tradition that the ancient inhabitants of the land had retreated to the hollow hills rather than give up their tongue carries considerable resonance. The Tylwyth Teg, on this reading, were a model of linguistic and cultural persistence: a people who had kept their language intact through every change that the world had brought.

Primary Sources and Further Reading

• Gerald of Wales, Itinerarium Cambriae (c.1191), translated as The Journey Through Wales (Penguin Classics). The primary and most significant source for the story of Elidurus and the fairy language, recorded within a generation of the events Gerald describes and based on accounts from named ecclesiastical informants.
• John Rhys, Celtic Folklore: Welsh and Manx (Clarendon Press, Oxford, 1901). Contains the most sustained scholarly analysis of the Elidurus account and its relationship to wider Welsh beliefs about the fairy people as the ancient original inhabitants of the land.
• Wirt Sikes, British Goblins: Welsh Folk-lore, Fairy Mythology, Legends and Traditions (Sampson Low, Marston, Searle and Rivington, 1880). Discusses the Elidurus tradition within the broader Victorian survey of Welsh fairy belief and the Tylwyth Teg's relationship to the Otherworld.
• Elias Owen, Welsh Folk-Lore: A Collection of the Folk-Tales and Legends of North Wales (Woodall, Minshall and Co., 1887). Provides supplementary Welsh accounts of the fairy language tradition and the understanding of the Tylwyth Teg as ancient pre-human or pre-Celtic beings.

Note: The scholarly interpretation that the Tylwyth Teg represent a folk memory of pre-Celtic inhabitants of Britain is one hypothesis among several. While it has been advanced by scholars including John Rhys, it is not the consensus position in modern Celtic studies, and the characterisation here reflects the Welsh folk tradition's own understanding rather than an established historical claim.

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