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The Brehon Laws

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Brehon law is the usual term for Irish native law, as administered in Ireland down to almost the middle of the seventeenth century, and in fact amongst the native Irish until the final consummation of the English conquest. It derives its name from the Irish word Breitheamh (genitive Breitheamhan, pronounced Brehoon or Brehon) which means a judge.

That we have ample means for becoming acquainted with some of the principal provisions of the Brehon code is entirely owing to the labours of two men, O'Curry and O'Donovan, who were the first Irish scholars since the death of the great hereditary Irish antiquarian, Duald Mac Firbis (murdered by an English settler in 1670), to penetrate and understand the difficult and highly technical language of the ancient law tracts. After much laborious work in the libraries of Trinity College Dublin, in the Royal Irish Academy, in the British Museum, and in the Bodleian Library at Oxford, O'Curry transcribed eight volumes full of the so-called Brehon Laws containing 2,906 pages, and O'Donovan nine more volumes containing 2,491 pages. Nor was their labour by any means exhaustive. There are many more valuable Brehon documents still untranscribed in the library of Trinity College, in the British Museum, and in the Bodleian, and possibly some fragments in the Royal Irish Academy and other repositories. From the labours of O'Donovan and O'Curry the Government published in the Master of the Rolls series five great tomes and a sixth containing a glossary. But these five large volumes do not by any means contain the whole of Irish law literature, which, in its widest sense, that is, including such pieces as the "Book of Rights", would probably fill at least ten such volumes.

Contents of the Brehon Law books

The first two volumes of the Brehon Law, as published, contain the Seanchus Mór (Shanahus More) or "Great Immemorial Custom" which includes a preface to the text, in which we are told the occasion of its being first put together and "purified", and the Law of Distress, a process which always had much influence in Irish legislation. The second volume contains the Law of Hostage Sureties, also a very important item in ancient Irish life, the law of fosterage, of tenure of stock, and of social connections. The third volume contains the important document known as the "Book of Acaill" which is chiefly taken up with the law of torts and injuries. This book professes to be a compilation of the various dicta and judgments of King Cormac Mac Airt who lived in the third century, and of Cennfaeladh, a famous warrior who fought in the Battle of Moyrath (c. 634), and afterwards became a renowned jurist, who lived in the seventh. The fourth and fifth volumes consist of isolated law tracts, on taking possession, on tenancy, right of water, divisions of land, social ranks, the laws relating to poets and their verse, the laws relating to the Church, chiefs, husbandmen, pledges, renewals of covenants, etc.

Although all these tracts go commonly under the generic name of the Brehon Laws, they are not really codes of law at all, or at least not essentially so. They are rather the digests or compilations of generations of learned lawyers. The text of the Seanchus Mór, for instance, which is contained in the first two volumes, is comparatively brief. That part of it relating to the law of immediate seizure must, according to M. d'Arbois de Jubainville, have been written before the year 600, but not before the introduction of Christianity into Ireland, which probably took place in the third century. The rest of the Seanchus is not so old. The year 438 is that given by the Irish annalists themselves for the redaction of the Seanchus Mór which according to its own commentary was the joint effort of three kings, of two clerics, of Ross a doctor of the Bérla Féine or legal dialect, of Dubhthach a doctor of literature, of Fergus a doctor of poetry, and of St. Patrick himself, who struck out of it all that "clashed with the law of God". It is impossible to say how far certain parts of the law may have reached back into antiquity and become stereotyped by usage before they became stereotyped in writing. The text of the Seanchus Mór itself is not extensive. It is the great amount of commentaries written by generations of lawyers upon the text, and then the additional annotations written upon these commentaries by other lawyers, which swells the whole to such a size.

Irish social organization

We are able to gather fairly well from these books the remains only of what must once have been an immense law literature, the social organization of a pure Aryan people, closely cognate with the ancestors of the modern Gauls, Spaniards, and Britons; and from what we learn of the ancestors of the present Irish people we may deduce a good deal that is probably no less applicable to the other Aryan Celts.

Broadly speaking, the country was governed by a ruling class called "Kings", of different grades, the highest being the King of Ireland, and next to these were the nobles or princes called in Irish Flaith (pronounced like flah or floih). In all there were, including kings and flaiths, nominally at least, seven different kinds of aires (arras), or nobles, and provision was carefully made that a wealthy farmer, or peasant grown rich through cattle, could, if he possessed twice the wealth of the lowest of the seven, and had held it for certain generations, become an aire, or noble, of the seventh, or lowest degree. Thus wealth and descent were carefully balanced over against each other. "He is an inferior chief whose father is not a chief", says the law. But it took care at the same time not to close to anyone the avenues to chieftainship. Under ancient Irish law the land did not belong to the king or the chief or the landlord, but to the tribe, and the lowest of the free-tribesmen had as much an inalienable right to his share as had the chief himself. In process of time parts of the tribal territory appear to have become alienated to subtribes or families, and the chief, who always exercised certain administrative duties with respect to the land, appears to have had certain specific portions of the tribal land allotted to himself for his own use, and for the maintenance of his household and relatives. He was in no sense, however, what is now known as a landlord, although the whole tendency of later times was to increase his power at the expense of his tribe and vassals.


The great bulk of the ancient Irish cultivators were the Féine (Faina) or free-tribesmen from whom the Brehon law is called in Irish Féineachas, or the "Law of the Free-tribesmen". In process of time many of these in hours of distress naturally found themselves involved in something like pecuniary transactions with their head-chiefs, and, owing to poverty, or for some other reason, were driven to borrow or accept cattle from them, either for milk or tillage. These tribesmen then became the chieftain's céiles (kailas) or vassals. They were known as Saer-stock and Daer-stock Céiles. The Saer-stock tenant — saer means free in the Irish language — accepted only a limited amount of stock; and retained his tribal rights, always most carefully guarded by the Brehon law, in their integrity. But the Daer-stockdaer means unfree — tenant, who took stock from his chief, became liable for heavier but still carefully defined duties. For instance for every three heifers deposited with him by his chief, he became liable to pay his chief the "proportionate stock of a calf of the value of a sack with its accompaniments", and refections for three persons in the summer, and work for three days. The tribesman, it will be observed, by accepting stock from his chief parted to some extent with his freedom, but his interests were carefully looked after by law, and it was provided that after food-rent and service had been rendered for seven years, if the chief should die, the tenant should become entitled to the stock deposited with him. If, on the other hand, the tenant died, his heirs were partly relieved from their obligation. It will be observed that while this to some extent resembles the well-known Metayer system, so common on the continent of Europe, where the landlord supplies the stock and the land, and the tenant the labour and the skill, it differs from it in this, namely that in Ireland the saer- and daer-stock farmer did not supply the land, which was theirs by right of their free tribesmanship. In this way, namely, by accepting stock from their overlords, a rent-paying class grew up in Ireland, to which undoubtedly in time a large proportion of the ancient Irish came to belong, but the rent was paid not for the land but for the chief's property deposited with the tenant.

But outside of the Free-tribesman (the Féine and Céile) there grew up gradually a class of tenants who were not free, who in fact must have been in something very like a state of servitude. These were known by the name of fuidirs or bothachs, i.e. cottiers. They appear to have been principally composed of broken men, outcasts from foreign tribes, fugitives from justice, and the like, who, driven out of or forsaking their own tribes, sought refuge under some other chief. These men must have been natural objects of suspicion if not of detestation to the free tribesmen, and, being themselves absolutely helpless, and having no tribal rights of their own, they became entirely dependent upon their chief, who settled them down upon the outlying or waste lands of the tribe, or possibly at times upon his own separate land which as chief he held in severalty, and imposed upon them far heavier tolls or rents than the law permitted to be exacted from any other members of the tribe. As Ireland became more troubled by Northmen, Normans, and English, this class of tenant increased in numbers, so many tribes were broken or destroyed, and the survivors dispersed to find refuge in other tribes and under other chiefs. In this way there grew up gradually, even under Irish law, a body of tenants to whom their chiefs must have stood in the light of something like English landlords.

The Irish family or fine

A curious Irish social unit was the fine (finna), consisting of one group of five persons and three groups of four, all males. The head of the family, called the ceann-fine (Kan-finna), and four members made up the first group, called geil-fine, the other three groups of four each were called deirbh-fine (true family), iar-fine (after family), and inn-fine (end family). On the birth of a new male member in the geil-fine the eldest member of the group was moved up into the next four (the deirbh-fine), and one out of that four into the next four, and one out of the last four was moved out of the fine altogether, into the clan, or sept, this last male thereby ceasing to be a member of the family, or fine. The sept, to use the English term, sprang from the family, or the family after some generations grew into the sept and then into the clan, contracting a greater share of artificiality in proportion to its enlargement. Because, while all the members of the sept could actually point to a common descent, the descent from a single ancestor in the case of the whole tribe was more or less founded upon fiction. The portion of territory ruled over by a sub-king was called tuath (too-a) and contained within it, at all events in later times, members of different descents. The chief, both of the tuath and the sept, was elected by the tribe or clansmen. The law of primogeniture did not obtain in Ireland, and the selection was made of the man who being of the chieftain's near blood could best defend the tribe and lead it in both war and peace. "The head of every tribe", says the Brehon Law tract the Cain Aigillne, "should be the man of the tribe who is the most experienced, the most notable, the most wealthy, the most learned, the most truly popular, the most powerful to oppose, the most steadfast to sue for profits and to be sued for losses." As early as the third century, in a well-known piece of Irish literature, Cairbre, afterwards King of Ireland, is depicted as asking his father Cormac Mac Airt the question: "For what qualifications is a king elected over countries and tribes of people?" And Cormac in his answer embodied the views of practically every clan in Ireland down to the beginning of the seventeenth century. "He is chosen", said the king, "from the goodness of his shape and family, from his experience and wisdom, from his prudence and magnanimity, from his eloquence and bravery in battle, and from the number of his friends." He was, however, always chosen from the near kindred of the reigning chieftain.

Irish criminal law

There seems to have been no hard and fast line drawn between civil and criminal offences in the Brehon law. They were both sued for in the same way before a Brehon, who heard the case argued, and either acquitted or else found guilty and assessed the fine. In the case of a crime committed by an individual all the sept were liable. If the offence were one against the person, and the criminal happened to die, then the liability of the sept was wiped out, for, according to the maxim, "the crime dies with the criminal". If, however, the offence had been one causing damage to property or causing material loss, then the sept remained still liable for it, even after the death of the criminal. This regulation resulted in every member of the sept having a direct interest in suppressing crime.

There was always a fine inflicted for manslaughter, even unpremeditated, which was called an eric. If the manslaughter was premeditated, or what we would call murder, the eric was doubled, and it was distributed to the relatives of the slain in the proportion to which they were entitled to inherit his property. If the eric were not paid, then the injured person or family had a right to put the criminal to death. This acceptance of a blood-fine or eric for murder was a great source of scandal to the English, but, as Keating points out in the preface to his history of Ireland written in Irish, it was really a beneficent and logical institution, made necessary by the number of tribes into which Ireland was divided. Nor was the punishment, though short of the capital one, by any means light, and it at least insured compensation to the murdered man's relatives, a compensation amounting to the entire "honour-price" of the murderer. For every man, from king to fuidir (the lowest class of tenant), had what was in Irish law termed his eineachlan, or honour-price, and this was forfeited in part or in whole, according to well-defined rules for various crimes. It was always forfeited for taking human life. Clergy we find more heavily punished than laymen. A man of high rank was always fined more than one of low rank for the same misdemeanour. An assault on a person of rank was more severely punished than one on an ordinary man. Fines for crimes against the person were particularly heavy; two cows, for instance, was the fine for a blow which raised a lump but did not draw the blood. The punishments awarded by the Brehons were of a most humane character. There is no trace of torture or of ordeal in ancient Irish law.

From the earliest times in which the English invaders made the acquaintance of the Brehon law system they denounced it with the most unsparing invective. But all the Norman chiefs who ruled over Irish tribal lands governed their territories by it in preference to English law, and in Elizabeth's reign the great Shane O'Neill pointed out with bitter irony that if his Irish laws were so barbarous as the queen's ministers alleged, it was passing strange that three hundred families had migrated from the English pale and the beneficent operations of English law to take refuge in his dominions. As early as 1367 an English Statute of Kilkenny denounced Brehon laws "wicked and damnable". "Lewd" and "unreasonable" are the epithets applied to it by Sir John Davies. "In many things repugning quite both to God's law and man's" is how the poet Edmund Spenser characterized it.

The student, however, who views these laws dispassionately today, and merely from a juridical point of view, will find in them, to use the words of the great English jurist Sir Henry Maine, "a very remarkable body of archaic law unusually pure from its origin". It is, in fact, a body of law that reflects for us early Aryan custom in its purity, almost perfectly untainted or uninfluenced by that Roman law which overran so much of the rest of Europe. It is true that Brehon law does bear certain resemblances to Roman law, but they are of the slightest, and not even so strong as its resemblance to the Hindoo codes. It has in truth certain relations to all known bodies of Aryan law from the Tiber to the Ganges, some to the Roman laws of earliest times, some to the Scandinavian, some to the Slavonic, and some particularly strong ones to the Hindoo laws and quite enough to old Germanic law of all kinds "to render valueless", to use the words of Sir Henry Maine, "the comparison which the English observers so constantly institute with the laws of England". "Much of it", says Maine, "is (now) worthless save for historical purposes, but on some points it really does come close to the most advanced legal doctrines of our day". "There is a singularly close approach", he remarks in another place, "to modern doctrines on the subject of contributory negligence, and I have found it possible to extract from the quaint texts of the 'Book of Acaill' some extremely sensible rulings on the difficult subject of the measure of damages, for which it would he in vain to study the writings of Lord Coke though these last are relatively of much later date". But he points out how heavily the Brehon Law pays in other respects for this striking anticipation of the modern legal spirit by its too frequent air of fancifulness and unreality and indulgence of imagination. In the "Book of Acaill", for instance, which, as mentioned before, is chiefly concerned with the law of torts, we find four long pages concerned solely with the injuries received from dogs in dogfights — Ireland was famous for its hounds, and dog-fights figure more than once in old Irish literature — setting forth in the most elaborate way all the qualifications of the governing rule required in the case of owners, in the case of spectators, in the case of the "impartial interposer", in the case of the "half-interposer", that is the man who tries to separate the dogs with a bias in favour of one of them, in the case of an accidental onlooker, in the case of a youth under age, and in the case of an idiot. The Brehons, in fact, appear to have never hesitated about inventing or imagining facts upon which to base their theoretical judgments. They endeavour to deal with all cases and all varieties of circumstances, and they have special rules for almost every relation of life and every detail of the social economy. A great number of the cases which come under discussion in the law books appear to be rather problematical than real, cases propounded by a teacher to his pupils to be argued on according to general principles, rather than actual subject for legal discussion.

Origin and gradual growth

Ancient Irish law was not produced by a process resembling legislation, but grew up gradually round the dicta and judgments of the most famous Brehons. These Brehons may very well have been in old times the Irish equivalents of the Gaulish Druids. There were only four periods in the entire history of Ireland when special laws were said to have been enacted by legislative authority: first during the reign of that Cormac Mac Airt already mentioned, in the third century; second, when St. Patrick came; third, by Cormac mac Culinan, the King-Bishop of Cashel, who died in 908; and lastly by Brian Boru, about a century later. But the great mass of the Brehon code appears to have been traditional or to have grown with the slow growth of custom. The very first paragraph of the Law of Distress takes us back to a case which happened in the reign of Conn of the Hundred Battles in the second century, and this passage was already so antique at the close of the ninth century that it required a gloss, for Cormac mac Culinan (who died in 908) alludes in his glossary to the gloss upon this passage. There are many allusions in this glossary to the Seanchus Mór, always referring to the glossed text, which must consequently have been in existence before the year 900. The text of the Seanchus Mor relies upon the judgments of famous Brehons such as Sencha in the first century, but there is no allusion in its text to any books or treatises. The gloss, however, is full of such allusions. Fourteen different books of civil law are alluded to in it. Cormac in his glossary alludes to five. Only one of the five alluded to by Cormac is among the fourteen mentioned in the Seanchus Mor. This shows that the number of books upon law must in old times have been legion. They perished, with so much of the rest of Irish literature, under the horrors of the English invasion and the penal laws, when an Irish manuscripts was a source of danger to the possessor.

The essential idea of modern law is entirely absent from the Brehons, if by law is meant a command, given by some one possessing authority, to do or to forbear doing a certain thing under pains and penalties. There is no sanction laid down in the Brehon laws against those who violated them, nor did the State provide any such sanction. This was the great inherent weakness of Irish jurisprudence, that it lacked the controlling hand of a strong central government to enforce its decisions. It is a weakness inseparable from a tribal organization in which the idea of the State, which had begun to emerge under the early Irish kings, had been repressed. When a Brehon had heard a case and delivered his judgment, there was no machinery of law set in motion to force the litigant to accept it. The only executive authority in ancient Ireland which lay behind the decision of the judge was the traditional obedience and good sense of the people, and it does not appear that this was ever found wanting. The Brehons never appear to have had any trouble in getting their decisions accepted by the common people. The public appear to have seen to it that the Brehon's decision was always carried out. This was indeed the very essence of democratic government, with no executive authority behind it but the will of the people. There can be no doubt whatever that the system trained an intelligent and law-abiding public. Even Sir John Davies, the Elizabethan jurist, confesses "there is no nation or people under the Sunne that doth love equall and indifferent justice better than the Irish; or will rest better satisfied with the execution thereof although it be against themselves, so that they may have the protection and benefit of the law when upon just cause they do desire it".

Influence of the Catholic Church upon Brehon Law

With regard to the influence of the Catholic Church upon Irish law as administered by the Brehons it is difficult to say much that is positive. Its influence was probably greatest in a negative direction. We have seen that the Brehons claimed the sanction of St. Patrick for the laws contained in the Seanchus Mór. We may also take it for granted that it was owing to the introduction of Christianity that Irish law began to be written down. The Gauls, as Caesar tells us, had a superstition about committing their sacred things, which of course included their law, to writing, and if the Irish had the same, as is very probable, it did not survive the introduction of the Christian religion. Then the eric-fine for homicide, although it probably did not owe its origin to Christianity, yet supported itself "as a middle course between forgiveness and retaliation" by the case of one Nuada who had murdered St. Patrick's charioteer, being put to death for his crime and Patrick obtaining heaven for him. "At this day", says the text, "we keep between forgiveness an retaliation, for as at present no one has the power of bestowing heaven, as Patrick had at that day, so no one is put to death for his intentional crimes so long as eric-fine is obtained, and whenever eric-fine is not obtained he is put to death for his intentional crimes, and exposed on the sea for his unintentional crimes." Sir Henry Maine seems to think that the conception of a Will was grafted upon the Brehon Law by the Church, but if this were so, one would have expected that the law terms relating to it would have been derived from Latin sources; this, however, is not so, the terms being of purely native origin. In another most important matter, however, the Law of Contract, the Church may have exercised a greater influence; the sacredness of bequests and of promises being equally important to it as the donee of pious gifts. It is also likely that much of the law relating to the alienation of land, all the land belonging originally to the tribe, was influenced by the Church, and indeed the Church seems to have been the grantee primarily contemplated in these regulations. There is a great mass of jurisdiction relating to its territorial rights, and no doubt this must have affected the outside body of law as well. But all bodies of law are exceedingly unmalleable, and tend to resist the absorption of foreign elements; and Sir Henry Maine's conclusion is that "there has certainly been nothing like an intimate interpenetration of ancient Irish law by Christian principle". Still the effect of Christian principles must certainly have been great, but they were probably powerful as a negative rather than as a positive factor.

Extinguished by the English

The Brehon law code was ultimately extinguished by the English in every part of Ireland. So soon as they conquered a territory they stamped it out, banished or slew the Brehons, and governed the land by English law. It would have been a very inconvenient doctrine for them that the tribe owned the land or that the people had rights as apart from the chief. Whenever a chief made his submission he was recognized as owner and landlord of the territory of the tribe, and the territory was adjudged to descend by primogeniture to his eldest son. In this way the hereditary rights of the mass of the people of Ireland were taken from them, and they were reduced to the rank of ordinary tenants, and, the native nobility being soon exterminated, they mostly fell into the hands of English landlords, and were finally subjected to those rack rents which have made the name of Irish tenant an object of commiseration for so many generations. The Brehon laws remained in force in every part of Ireland where the Irish held sway until the final conquest of the country. It has been shown that the system of land-tenure which the Fitzgeralds found obtaining in Munster in 1170 was left unchanged by them, and the land burdened with no additional charges until their subjugation in 1586. Duald Mac Firbis, the celebrated antiquary, who died in 1670, mentions that even in his own day he had known Irish chieftains who governed their clans according to "the words of Fithal and the Royal Precepts", that is according to the books of the Brehon Law. Amongst the many bitter injustices inflicted upon Ireland and the Irish by the English conquest none has had more cruel or more far-reaching effects than the abrogation of the Brehon law relating to land-tenure and division of property.


Brehon Laws (Master of the Rolls Series) 1, (1865); II (1869); III (1873); IV (1879); V and VI (1901); D'Arbois de JUBAINVILLE, Etudes sur le droit Celtique, avec la collobaration de Paul Collinet (2 vols. Paris, 1893); vol. I forms tome VII of M. D'Arbois' Cours de literature Celtique; MAINE, Early History of Institutions (London, 1875); GINNELL, The Brehon Laws, a legal handbook (London, 1894); HYDE, A Literary History of Ireland (London, 1903), xlii; Memorandum on Land tenure, appended to Third Report of the Commission on Congestion in Ireland, Government Blue Book (1907), 358, containing a brief but valuable summary of the secure and comfortable position of the masses in Ireland under the Brehon law system at the time of the confiscation of Munster, towards the close of the sixteenth century, and of the rack rents which followed the substitution of English law, by MRS. STOPFORD GREEN; JOYCE, A Social History of Ancient Ireland (Dublin, 1903); MEYER, Kultur der Gegenwart (Berlin, 1907), s.v. Keltische Literoturen.

About this page

APA citation. Hyde, D. (1907). The Brehon Laws. In The Catholic Encyclopedia. New York: Robert Appleton Company.

MLA citation. Hyde, Douglas. "The Brehon Laws." The Catholic Encyclopedia. Vol. 2. New York: Robert Appleton Company, 1907. <>.

Transcription. This article was transcribed for New Advent by Dr. Michael J. Breen — Trinity College, Dublin.

Ecclesiastical approbation. Nihil Obstat. 1907. Remy Lafort, S.T.D., Censor. Imprimatur. +John M. Farley, Archbishop of New York.

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