Ireland in prehistory

A concise account by Desmond Johnston

Early Ireland

Ireland's early history is dominated by the end of the last Ice Age. It has been mooted that perhaps in South West Ireland some hunter-gatherers remained in occupation during the Ice Age. However apart from that the first evidence we see for occupation appears in the River Bann area in North Ulster (Mountsandel - Toomebridge - Ballymoney). Such occupation -- per land-bridge or by water from West Scotland -- has been dated to around 7,000 BC. It is interesting to note that these early arrivals lived in quite substantial houses, and as well as being hunter-gatherers and fishermen practised a basic form of agriculture.

There would appear to be substantial gaps in our knowledge of the settlement of Ireland until around 4,000 BC. This marks the beginning of the megalithic period (as well as fitting into the Neolithic era.) Recent research done in Britain in which the teeth of ancient skeletons were analysed to determine diet indicates that around 4,000 BC there was a relatively sudden change in diet from fish to domestic animals. This would seem to indicate an arrival of new agricultural techniques from abroad, accompanied by changes in pottery, burial customs, beliefs, etc. It would be good to know whether a similar analysis in Ireland would produce a parallel result.

Ireland is unique in many ways in its cultural content. In the Iron Age, Britain and Western Europe were swamped by the Latin/Roman culture. In the Dark Ages this in turn was swept away to some extent by the coming of "barbarian" cultures. Thus W European and British traditions of Early Iron Age, Bronze Age, and earlier cultures were lost. Ireland was fortunate in avoiding the Roman steamroller and to a large extent Dark Age influences. It retained a body of oral tradition of its early history, now classified as mythology. Unfortunately that tradition was not preserved at the time in written form. From the time of St. Patrick the Church for some centuries tended to discourage such traditions as "the work of the Devil". A change of heart occurred around the 11th century and in monasteries the old mythology began to be recorded, but much had already been lost. Also there was said to be a tendency to make the mythology acceptable in Christian terms by relating people and events in Irish early history to people and events in the Bible.

This leaves us with an interesting problem. If there are references in Irish mythology today to Mediterranean and Middle Eastern countries do we disregard them as extraneous material or do we accept the fact that in the ancient world there was a lot more mobility than we tend to imagine? There are too many indications in archaeology of culture- movement -- people-movement to discount traffic to and from Ireland at an early stage. The truth may lie between the two.

The best known source which has survived is -- perhaps misleadingly -- called "the Book of the Invasions". (Lebor Gabala Erren). This and other sources deserve to be treated seriously as a basis for getting clues to the early history of Ireland. In such works there is a lack of chronological sequence, gross exaggeration, possible intrusion of "manufactured" events, magic, and all the stuff of mythology. Nevertheless there will be a hard core of real people and events. Another problem is that in the ancient world heroes tended to become "gods" and lose their earthly identity. (Classical Greece being a good example of this trend). Thus mythology can be regarded almost as a manifestation of religion. Imperfect as Irish sources are they are unique to Ireland and not to be discounted as a source of historical knowledge.

Megalithic Ireland

The NW European megalithic era is represented in Ireland on a very big scale. Great passage mounds, dolmens, stone circles, standing stones, alignments are all an important feature of the landscape. Each aspect of the megalithic of course tends to have its own unique "Irish" form, as is true for other megalithic areas -- Brittany and Scotland for example. It is as if each time a new culture came in contact with an existing culture the original inhabitants adapted and amended it to fit in with their ideas. Also Ireland possesses on a large scale examples of its own form of rock scribings, now generally agreed to represent astronomical events.

Newgrange Ireland
Newgrange passage mound in the Boyne Valley, Ireland

The passage mound building dates in Ireland would appear to be from around 3,500 BC. (That is -- in their present form -- they would have even earlier beginnings). As they stand they could be slightly later than Brittany and Iberia. Precise dating is hard to achieve as alteration and expansion would extend over a lengthy period. Passage orientation is by now generally accepted to tie in with solar, lunar, and stellar alignments. The term "passage graves" is on its way out. Even when used for burials that would not have been the original purpose -- any more than a cathedral is a tomb. Changes in farming leading to the need to understand the calendar and depend on it are the key to such monuments. It is significant that from Ireland to the Fertile Crescent agricultural change and the study of astronomy are contemporaneous -- from 4,000 BC megalithic Europe was in line with parallel developments in the Middle East. Considerable organization was required in such projects indicating a strong religious and political system and a reasonably large population with an economic surplus. (Made possible by new farming techniques).

Ireland is also well supplied with such features as dolmens and circles of standing stones. It seems to be generally agreed that such features of the European megalithic came after the passage mounds -- possibly in the region of 2000 BC. It is however interesting that Professor O'Kelly in Newgrange - Archaeology, Art, and Legend produced the argument that there is evidence that the stone circle at Newgrange predates the mound. If so, this could simply denote an individual exception -- or it could be of general application. Again the stone circles so prevalent in the British Isles and Western Europe are being studied from the aspect of astronomical orientation. It could well be that they will indicate an infinitely wider variety of astronomical sightings than the more rigid and limited passage mounds. Interestingly almost all are ovoid rather than circular, a characteristic shared with the older henge and related monuments.

Dolmens and individual menhirs or standing stones are particularly prevalent in Ireland. The construction of the former has involved the placement of massive capstones -- a major feat in many cases. It is presumed that all were covered with a layer of earth and small stones to form minor mounds and erosion has created the bare stone frameworks we see today. Each has an astronomical orientation -- particularly to the East. At some point in time they became used as tombs -- presumably for local chieftains or the families thereof. But whether or not they were constructed for this purpose originally is a moot point.

Allied to the dolmens are the chambered mounds with short passages, such as court cairns, with a ceremonial area marked out in front by stones in a horse-shoe shape. Again these, too, were at some point used as tombs, but their apparent provision for ceremonial gatherings and their astronomical orientation could give a clue as to their real function.

There is a general tendency for stone monuments, in Ireland as elsewhere, to appear in areas giving a wide view of the horizon, making an astronomical function the most likely. It has been suggested that such monuments are a legacy of the copper-using Beaker Culture of around 2,500 BC. However Ireland has been stated to have comparatively few indications of this culture.

On the question of outside influences on culture -- in recent years the concept of mass takeovers of a culture by invaders has been drastically revised in favour of a change in thinking largely induced by trade contact and by the arrival of relatively small groups of people. These could have been immigrants or "economic refugees" escaping from war, famine, natural disasters in their homeland. Of course armed incursions would have from time to time have taken place, but not on the scale often imagined in the past. This is where such titles as "The Book of the Invasions" reflect Victorian, rather than modern, thinking. The great battles as described in such literature are more likely to be relatively minor engagements precipitated by a natural tension between the new arrivals and those already in possession. Such episodes "improve with the telling" over generations.

Another point is that rather than being exterminated by the new arrivals the earlier inhabitants would lose land and status in many cases but over time the two groups would intermarry and merge. Another thought is that from time to time the incoming culture was often radically changed by the prior inhabitants. It is interesting that recent scientific studies in the East of England have produced surprisingly little evidence of an "Anglo-Saxon" element in the current population.

From the Irish perspective the earliest "Irishmen" have been found to be located in the West of Ireland, and to have strong genetic links with the Iberian Peninsula, going back presumably to the beginnings of the megalithic. It is worth keeping in mind that the astronomical studies of the post-4,000 BC period would be equally applicable to navigation as to agriculture. Accounts of voyages such as the Aeneid, the Odyssey, and the Argonauts have many references to star navigation -- they did not have to wait for the compass.

A somewhat dated -- but nonetheless interesting -- book is Sophie Bryant's "Celtic Ireland." (Kegan Paul 1889). She produces an interesting analysis of the origins of the population of Ireland in each significant area -- with Ulster largely represented by "Belgic" stock, with the exception of areas of Lagan Valley, S Donegal, Tyrone, Fermanagh where the dominant group is "Ugrian" originating in Scotland. Connaught plus SE Ireland she represents as" Celtiberian", of Iberian coastal origin. From the centre of the E coast across to SW Ireland she gives the origin of the population as "Pure Celtic" with origins in Gaul, NE and Central Spain, Central Europe, N Greece. It could be interesting, using modern techniques, to check out these ideas -- typical Victorian reliance of course on the use of the word "Celtic."

Ancient Ireland - Outside Influences

There is a tendency to dismiss such sources as the "Book of the Invasions" as "mythology" and as such not relevant to the work of archaeologists and historians. This in spite of the work in the 19th century of Schliemann in Troy and Mycenae and of Evans in Crete. Both followed their dream that behind mythology there lies historical fact. With the tools of archaeology it is possible to see through the added gloss of the story-teller over the ages. A problem with mythological traditions in Ireland as elsewhere is a tendency to attribute to them a religious/magical/spiritual significance. This can tend to discourage analysis -- perhaps inspired by a fear that they would lose something if proved to have a factual/historical basis. This however I feel is an unjustified apprehension -- they will always be great stories.

The main source which I will be referring to here is "The Book of the Invasions" selecting some relevant and salient points. It would be too much to expect that the doings of a relatively small group of people who may have survived the rigours of the Ice Age in SW Ireland should be recorded in mythology. Nor can we expect the first immigration from SW Scotland to the R. Bann/Mountsandel area around 7,000 BC to be mentioned. Every culture does however have some record of its early inhabitants and in the case of Ireland these are represented by the followers of Cesair, of Partholon, and the Fomorians.

Cesair and Partholon

Here we have an attempt to explain the earliest arrivals. Both groups were wiped out by natural disasters -- flood and plague respectively. Flood can be interpreted as a "Biblical" reference added when the mythology was put in writing. However when looking at ancient cultures world-wide the "flood legend " is universal. This would not refer to the same inundation as in the Sumerian and Hebrew tradition but geological and other evidence tend to back up the destruction by water theory in different places and at different times. In addition the presence of plague in the world is all too familiar. And of course there are always survivors who live "to tell the tale".

In Partholon's time "seven lakebursts" occur. It would be useful to know to which natural or man-made causes these can be attributed -- or indeed what the term means. Flooding or the result of irrigation? There is evidence for the sudden emergence of lakes as a result of earthquakes. Plains were cleared for farming. This could represent the introduction of farming from outside in the Neolithic era. Partholon's people are credited with the introduction of the first cattle and ploughs - -again a specific aspect of the Neolithic Revolution. Early farmers in particular were vulnerable to diseases of livestock and weather-induced crop failure (= plague?) Houses, cauldrons, guest-houses and ale were among the achievements of this group. (Cauldrons = Copper Age?) The home of this group was reputedly "Greece". We cannot put too much weight on the geographical names used in mythology but Neolithic technology would have had a source of inspiration in the general Mediterranean area. It does not take a big number of people with new ideas to change the life-style of a whole country.


The plague-depopulated land was next visited by the followers of Nemed -- supposedly of Scythian origin. Former achievements had to be repeated. Again there were "lakebursts" (a good or a bad thing?) and further land clearance. The lakebursts were accompanied by a "pestilence of fire" and a rushing noise. (Seismic activity - comets - meteors?) Collision occurred between the followers of Nemed and the "Fomorians". This could well have represented sheepmen versus cattlemen or herdsmen versus agriculturalists.

Nemed's followers were defeated and scattered in various directions. (1) Some departed to "the North of the world" -- Scotland/Scandinavia? Perhaps they returned generations later as Tuatha de Danann. (2) Some settled in "the North of Alba" -- North Britain. (3) Some went to" the land of the Greeks" where they suffered slavery, being made to carry soil up hillsides in leather bags to create new agricultural land. One can easily relate this to the eroded slopes of Greece. It is said that when the Phoenicians occupied the barren island of Malta they imported shiploads of soil for farming. (4) A group stayed in Ireland to survive as best they could.

Fir Bolg

The term Fir Bolg is used to represent the next group to influence Ireland's prehistory. These represent one group of Nemesians. The Fir Bolg themselves took over Connaught and Munster. The Fir Domnan occupied Leinster. The Fir Galioin went to Ulster.

The Fir Bolg are credited with establishing the first effective system of law and justice in Ireland. An interesting comment is made that during this period a change took place in Ireland's trees with "straight" trees ( Conifers?) being replaced by "knotted" trees (deciduous?). Perhaps an indication of climate changes which we know took place? The Fir Bolg were supplanted by the next culture to impact on Ireland -- the Tuatha de Danann.

Tuatha De Danann

This new infusion of life-blood into Ireland is the one which has suffered most from the shortcomings of myth. Their technology, particularly in metalcraft, their learning, military skills, etc. have become distorted into "magical" attributes. Their leadership became sanctified -- deified -- by subsequent generations.

They were reputedly a fair-haired race different from the Iberian characteristics of the most ancient Irish. They came from -- or via -- the Northern world. All the indications are that they were representatives of a Bronze Age culture. A Middle Eastern origin has been suggested too -- a source of Bronze Age culture. Their name has been associated with the goddess Dana -- a recurring name as in the rivers Don and Danube, in the old name for the Greeks (Danaos), in the Danaoi -- one of the groups known as the Peoples of the Sea, and in Denmark.

They are identified with an intellectual - druidic class who were trained in religious, legal, astronomical skills among others., which system, alongside other aspects of their culture, was later adopted by the Iron Age Celts.

They were opposed by the Fomorians whom they eventually defeated, and with whom interestingly they had some common points of origin. The remaining Fir Bolg population they confined to Connaught.

A whole body of "theology" grew up around the leaders of the Tuatha de Danann who included such names as the Dagda, Oengus, Lug, Manannan mac Lir, Ogma, Goibniu, Dian Cecht, and Creidne. This subsequent "deification" is a tribute to the impact of the superior skills and knowledge of this gifted race. As a people they were associated with light and the sun.

Eventually they were supplanted by yet another culture, that of the Milesians. So great was the status of the Tuatha de Danann it was deemed unthinkable that they should vanish from human ken and they acquired the status of immortality, being said to vanish into the already ancient and sacred passage mounds --the Sid -- whence they wandered the earth as spirits.


Having now "disposed of" the Fomorians it is a good time to review their influence on Ireland. Chronologically they do not fit easily into our picture. They appear first in the antique period of Partholon and continue to reappear until their ultimate defeat by the Tuatha de Danann. Long as their tenure was they are not represented as the "aboriginal" Irish race but as a sea-roving people who established themselves on a base in Tory Island, off the Donegal coast. Their influence seems over the years to have extended over a large part of the country. Sheep-farmers in life-style, they are given a "bad press" by their more civilized (?) rivals. Thus we hear they were associated with evil - night - death. They are described as grotesque -- sometimes with one arm, one eye, one leg. Interestingly there are drawings of the "unusual" people found in the West Indies and in America after Columbus which have many points in common with the Fomorians! (Psychological reaction to the new - unfamiliar - and therefore terrifying) .They were also stated to practise child sacrifice, not unknown among many ancient peoples, and certainly attributed to the Phoenicians/Carthaginians -- another seafaring race and avid colonists. The name of one of their leaders -- Balor -- has been suggested as being derived from the Phoenician/Carthaginian god Baal (also spelt Bealiah). As sea-rovers they are also suggested to have a Scandinavian origin. (Rock scribings in Norway indicate the use of quite large ships from the Bronze Age at least).

Mound of the Hostages - Hill of Tara
Mound of the Hostages - Hill of Tara


If the coming of the Tuatha de Danann represents the coming of the Bronze Age to Ireland then the arrival of the Milesians embodies the Iron Age. The story of their wanderings before reaching Ireland is an elaborate one. It is generally assumed that they -- or at least their culture -- were Celtic in origin. Their point of origin, for what it is worth, is Scythia in SE Europe. Part of their mythology is made to associate them with Egypt at the time of the Exodus, but this chronology would upset Celtic/Iron Age connections. Again we could be looking at an extraneous Biblical connection. They could of course have been "proto-Celts" -- that period in Egypt and the Mediterranean is chaotic with the eruption of Thera, the Trojan War, and the Sea Peoples -- so confirmatory evidence is hard to find. Perhaps two similar cultures 1000 years apart did find their way to Ireland post -- Tuatha de Danann? In any case the Celtic/Iron Age dating is feasible, since Celtic (and possibly Scythian) units of mercenaries did serve in the Egyptian army and the Celts are on record for striking for better pay.

One way or another a group of Milesians reached Ireland via Spain and confrontation with the Tuatha de Danann led to the defeat of the latter. This would seem to be an oft-repeated example of the superiority of iron weapons over bronze just as the bronze spears and swords of the Tuatha de Danann were superior to the wooden weapons of their predecessors.

Contributions of the Milesians to Irish culture -- apart from the introduction of iron implements which greatly increased agricultural yield -- include fine craftsmanship in metal generally, astronomically-determined dates for popular assemblies, weaving of variegated-coloured cloth. Their astronomy and agriculture were both advanced.

In religious beliefs the Milesians differed from the Tuatha de Danann and their successors. The Milesians believed that material nature is above the gods. The only true gods were the sun, moon, water, air, day, night, sea, land. The resulting clash of religious concepts with those evolved from the Tuatha de Danann resulted in a compromise, in which the old hero-gods like the Dagda, Lug, Ogma, etc. were still revered, becoming an essential part of the Milesian/Celtic belief system. The Celtic association with the spirits of streams, springs, trees, etc. was established, perhaps not unlike similar ideas inherited from the Neolithic era.

The Milesians already had a strong cultural heritage, as embodied in the warrior-poet Amairgen. Poetry and harp music were particularly revered. They followed the Tuatha de Danann in the intellectual, religious, artistic, Druidic system with its privileged role in society.

As part of the militaristic Iron Age tradition hill-forts were established throughout the land. The Milesians were said to have divided Ireland into two halves administratively -- with the River Boyne being the dividing line. Celtic culture is associated in people's minds with the tribal system -- but this must have been equally true for most other cultures as well. However we seem to see from this time onwards a growing tendency for inter-tribal warfare based on points of honour and a desire to command more resources. The Milesians are said to have set aside the province of Leinster for the prior inhabitants. This however would presuppose their arrival in greater numbers than was probably the case.

This is just a personal interpretation of the relationship between the mythology and the history of Ireland. Much remains to be done in this field. The mythology is not incapable of being reconciled with historical/archaeological thinking. One must remember that such matters as chronological/geographical accuracy were not so important to the writers of the old traditions as they are to our prosaic/factual society of today. Since every Irishman is said to love a good fight, battles will tend to be magnified out of all recognition. An infiltration of new people with new ideas becomes an invasion.

If "no man is an island" the same can be said for Ireland. Seafaring goes back a long way into the past -- made safer by astronomical knowledge. The Mediterranean world was limited by deserts to the South and East, by forests to the North, by the Atlantic to the West. When groups of people were affected by natural disasters, crop failure, war, etc. sailing North-West out of the Straits of Gibraltar was not an impossible option. Ireland was not unknown to the ancient world -- nor was the ancient world unknown to Ireland. The numbers would have been small, but it does not take a great number of people to make a great impact if their culture has something to offer.

The old mythology will not help us with the great mounds -- by the Bronze Age they had become disused if still objects of veneration. Perhaps the "new technology" of the stone circles had overtaken them. There are interesting comparisons between Irish and Greek mythology. A "must" if you are interested in an interpretation of Irish mythology and its relation to Greek culture is 'The Irish Mythological Cycle' by H D'Arbois de Jubainville -- O'Donoghue and Co. Dublin 1903.

Natural disasters played a vital part in the movement of people. Ireland as well as the Northern world was affected by eruptions of Hekla in Iceland 2345 BC and 1,159 BC. The Mediterranean world was shattered by the eruption of Thera/Santorini, now dated at 1,628 BC. The sun "went out" on such occasion -- crops failed -- famine and disease were rampant -- "when the going got tough the tough got going". Comets and meteors were said to have similar side- effects. An excellent book on the effect of such disasters on both Ireland and the Mediterranean, written by Mike Baillie, dendrochronologist, of Queen's University, Belfast is 'Exodus to Arthur' (Batsford 1999).

We have to remember that the "races" of Irish pre-history did not disappear. Like the passage mound builders they were overtaken by new culture, new technology, etc. borne often by new arrivals -- just as likely to be peaceful traders or refugees as warriors. The "Celts" are a topic in themselves. There was a great Celtic expansion Southwards (Italy Greece Turkey) from around 500 BC. But more significant is the expansion of Celtic culture in the Iron Age in all directions. As we have seen, that culture owed something to the great megalithic culture of NW Europe as well as to that of the Tuatha de Danann for example. Were the Milesians of Celtic race? Perhaps not. Were they of Celtic culture? Definitely yes. Did they "flood out" the existing population of Ireland? Very unlikely. It is culture rather than race which is the issue in the case of the Celts -- and that includes language, religion, etc.

Death in Irish prehistory by Gabriel Cooney and Conor McHale Death in Irish Prehistory by Gabriel Cooney is a book about life and death over 8,500 years in Ireland. It explores the richness of the mortuary record that we have for Irish prehistory (8000 BC to AD 500) as a highlight of the archaeological record for that long period of time.

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