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Prefix Mac and O'



            The successive invasions of Ireland from Strongbow to Cromwell, culminating in the final destruction of the Gaelic order and the long drawn out subjection of the Irish people under the eighteenth century penal code, together with the plantations of foreign settlers and the more peaceful infiltration of Englishmen in the commercial life of the country, have made Irish surnames more mixed than those of a nation with a less disturbed history.  The situation can no doubt be paralleled in several mid-European states, but there is nothing comparable to it in any of our nearer neighbours such as England, France, Germany, Holland or Spain, where foreign names are exceptional and native ones are seldom hidden under alien guise.  This latter is a phenomenon which is extremely common in Ireland.


            It has often been stated that surnames were introduced into Ireland by King Brian Boru.  Though this cannot be accepted as historically accurate it is a fact that Ireland was one of the first countries to adopt a system of hereditary surnames; or perhaps it would be truer to say that such a system developed spontaneously.  At any rate the Macs and O's were well established as such more than a century before the coming of the Cambro-Normans or, as they are more usually called, the Anglo-Normans.

            It is hardly necessary to state that these prefixes denote descent, mac (son) indicating that the surname was formed from the personal name, or sometimes calling, of the father of the first man to bear that surname, while O names are derived from a grandfather or even earlier ancestor, ó or ua being the Irish word for grandson or more loosely male descendant.

            Many instances occur of Mac names and some of O names in the Annals, list of bishops and other records relating to the centuries between the time of St. Patrick and that of Brian Boru.  These, however, were not hereditary surnames, but merely indicated the father (or grandfather) of the man in question.  Thus to take, by way of example, two successors of St. Patrick in the see of Armagh, Torbac MacGormain (d. 812) and Diarmuid O'Tighearnaigh (d. 852), these were not members of families called MacGorman and O'Tierney, but were respectively son of a man whose baptismal name was Gorman and grandson of one who was christened Tierney.

            Prior to the introduction of surnames there was in Ireland a system of clan-names, which the use of surnames gradually rendered obsolete except as territorial designations.  Groups of families, many of them descended from a common ancestor, were known by collective clan-names such as Dál Cais (whence the adjective Dalcassian), Ui Máine (or Hy Many), Cinel Eoghain, Clann Cholgain, Corca Laidhe.  The expression "tribe-names", used by John O'Donovan in this connexion, is perhaps more expressive, though a more modern authority, Professor Eoin MacNeill, objected to this term as misleading.  In some cases the tribe-name did subsequently become the surname of a leading family of the clan or tribe, but as a rule this did not happen; and, as the tribe name was usually identical with the surname acquired by some quite unrelated sept in another part of the country, confusion is apt to arise.  Thus the Clann Daly embraced the O'Donnells and other northern septs, Clann Cahill became O'Flanagans etc., Munter Gilligan was chiefly composed of the O'Quins of Annaly and Hy Regan was the tribe name of the O'Dunns.  It would be outside the scope here to pursue this aspect of Gaelic nomenclature.  A brief account of it will be found in Woulfe's Sloinnte and it is more fully dealt with in MacNeill's Celtic Ireland.

            The location of the clans or tribes as well as ancient territories such as Thomond, Breffny and Ossory, is indicated on the Barony Map.

            A study of this map shows that many of the tribe names have been perpetuated in the names of baronies, some like Keenaght, Pubblebrien and Iraghticonnor easy to identify, but more hardly recognizable in their English guise as, for example Iverk (Ui Eirc), Tirerrill (Tir Oilella), and Tullyhaw (Teallach Eachdhach).

            The first of the major invasions of Ireland in historical times (1169-1172) resulted in the formation of a new set of surnames belonging to the Norman families which in due course became Hiberniores Hibernicis ipsis.  The old Latin cliché is applicable to the names as well as to the people who bore them, for no one to-day would regard Fitzgerald or Burke as any less Irish than O'Connor or MacCarthy.

            It was not until the eleventh century that family names as we know them came into general use in Ireland.  They were intended originally to perpetuate the name of some great man, whose descendants were proud to claim him as an ancestor.  The patronymic 'O', meaning descendant of or 'Mac' (often abbreviated 'Mc'), meaning 'son of' was prefixed to his name, and the compound was then handed down from father to son as a family name.  King Brian's grandnephew, Turlough, for example, wishing to perpetuate the memory of the hero of Clontarf called himself Turlough O'Brien, that is Turlough, descendant of Brian.  At about the same time an Ulster prince descended from King Niall of the Nine Hostages styled himself Donal O'Neill.  These names forthwith became hereditary in their respective families, thus asserting the claim of those who whore them in later generations to descend from the royal stock of Niall, one of the greatest of Ireland's pre-patrician kings, or of Brian Boru, the most illustrated of her Christian monarchs.

            Names in this category are numerous and widespread in Ireland, and most of them have in the course of time become exclusively Irish, as for example Burke, Costello, Cusack, Cogan, Dalton, Dillon, Fitzgerald, Keating, Nagle, Nugent, Power, Roche, Sarsfield, and Walsh.  Some of them of course, like Barry and Purcell, though generally regarded as Irish, are found in England also since the twelfth century.  To-day, no doubt, almost all the Norman-Irish surnames which are increasingly common in England became established there as a result of nineteenth century and particularly or recent emigration from Ireland.

            The second great upheaval, five hundred years later, was of a more devastating character.  In the seventeenth century the dire effects of conquest were intensified by religious persecution and the three main events of that century resulting from military aggression--thethe Plantation of Ulster, the Cromwellian Settlement, and the Williamite forfeitures--followed by the Penal Code which was at its severest in the first half of the eighteenth century, inevitably led to a lock of accord between the new settlers and the old inhabitants of the country.  The natural process of assimilation was thus retarded, indeed it is not too much to say that it was deliberately prevented.  Thus the Elizabethan immigrants and those that followed them in the next century did not become hibernicized as the Normans had.

            A feature of the degradation of the Gael and the inferiority complex it produced was the wholesale discarding of the distinctive prefixes O and Mac.  Nor was this confined to the down-trodden peasantry.  The few Catholic gentry who managed to maintain to some extent their social position, while keeping their O's and Macs within the ambit of their own entourage (usually in the remoter parts of the country) were so depply conscious of belonging to a conquired nation that they frequently omitted the prefixes when dealing with Protestants, not only in legal matters but also in ordinary social intercourse.  Thus we find Daniel O'Connell's uncle, that picturesque figure universally known as "Hunting Cap", signing himself Maurice Connell as late as 1803 when approaching the Knight of Kerry to enlist his influence in a court case; while MacDermot, Chief of the Name, though ranking as a prince among his own people and himself a prominent banker in the middle of the eighteenth century, invariably signed himself simply Anthony Dermott.

            It can be truly said that the 17th century saw the curtain begin to fall on Celtic Ireland.  Events such as the Plantation of Ulster, the Cromwellian invasion, the Williamite Wars and the Penal Laws profoundly affected all aspects of life including the personal and family names of people.  For one thing use of the English language, originally introduced into Ireland by the Norman’s in the twelfth century began to gather momentum and resulted in Gaelic names being abandoned in many instances for anglicised equivalents.  Thus instead of the ancient Gaelic name O'Coraihegan, the forms Carchan, Carekin, Cargan, Cargin, Carigan, Carkin, Caroken, Carroughan, Carragan, Carraghan, Carrason, Carregan, Carrigan, Carrigeen, Carrison, Carroghan, Carroocan, Carrookan, Carrucan, Carson, Carsons, Cherson, Chrisham, Chrisney, Coarigan, Coorakan,Cooregan, Corcam, Corcon, Corgan, Corican, Corigan, Corkan, Corkane, Corken, Corkens, Corken, Corkins, Corkmich, Corocan, Corogan, Corragan, Corriagn, Corrican, CORRIGAN, Corrigin, Corrikan, Corrison, Corrogan, Corskin, Courakin, Crackan, Cracken, Crackin, Craggen, Craghan, Craigan, Craqckin, Crawson, Creagan, Creaghan, Creaghane, Creaghmile, Creagmile, Creegan, Creeshon, Cregan, Creggan, Creghan, Creigan, Creighan, Cresham, Cresken, Criagan, Cricken, Crieghan, Criggan, Criggans, Criggeen, Crighan, Crisham, Crishan, Crishim, Crishnahan, Croakin, Crockan, Crogan, Croghan, Crogin, Croken, Crookshank, Crookshanks, Crosenton, Crosin, Croskan, Crosner, Crossan, Crossane, Crossaun, Crossen, Crossin, Crujm, Crushim, Currigan, Curraghan, Curraken, Currigan, Currisken, Cursan, Curson.  There could be a multitude of variants of the same surname on record with members of the same family frequently using a different form of the name.  The great variety of English variants, each as valid as the next since there was no standardisation, is in sharp contrast to the single Gaelic form standardised by a thousand years of usage.

            A number of reasons conspired to bring about the multiplicity of variants resulting from the Anglicisation of Gaelic Names, in the first place the English language, being of Teutonic origin, lacked the refinement of the vowel sounds of the Gaelic, a factor which when combined with the great variety in regional dialect and accent, often produced wholly different versions of the same Gaelic surname.  The prevailing illiteracy added to the confusion and resulted in the severe corruption of many surnames.  To take an example:  The Gaelic MacEoin, anglicised McKeon and McKean, was corrupted to Muckian, and subsequently by pseudo-translation became Piggott, from the Gaelic word 'Muc' meaning 'pig'! In the exodus of the forties resulting from the great Famine, many who sailed to the New World had to endure further mutilation of their surnames at the hands of immigration officials where Anglicisation has so changed the original forms of Irish names that identification with the past, and sometimes even with the land of their origin, is difficult, if not impossible, unless the owners have retained a direct family tradition.

            It has been stated that one of the causes of the disuse of the prefixes Mac and O in the eighteenth century was the inclusion in the Penal Code of a provision to that effect.  No such clause in any of the relevant Acts can be found.  No legislation dealing with this question was ever passed except in so far as the Statute of Kilkenny (1367) affected the Irish of the Pale.  This indeed had no bearing on the use of Mac and O; but it did, no doubt, mark the beginning of the practice of translating Irish names into English, which in the eighteenth and nineteenth centuries became widespread and, I may add, proved more often to be mistranslation than translation.  Nevertheless pressure was exerted in other ways to bring about the degaelicization of surnames.  For example, even two generations before the Penal Code was in full force we find O'Conor Roe entering into a composition in which he binds the Irish chiefs under his influence to "forego the customs and usages of the Brehon law...and to give up prefixes to their surnames".  We may be sure that this undertaking was made by O'Conor with his tongue in his cheek and that it was ignored, but serves to indicate the official outlook in this respect.

            I may refer here to the widespread belief outside Ireland that Mac is essentially a Scottish prefix.  To us this idea is absurd, for many of our foremost Irish families bear Mac names such as MacCarthy, MacDermot, MacGuinness, MacGrath, MacGillycuddy, MacKenna, MacMahon, MacNamara, and so on.  Nevertheless, it is a fallacy widely held.  It is true, of course, that many Mac names in Ulster are Scottish in origin having come in with the seventeenth century planters; and these tended to retain their Gaelic prefix when those of Catholic Ireland fell into disuse.  In any case the Scottish Gaels are originally of Irish stock and Scotland herself took her name from the word Scotia which in Latin was at first used to denot the land inhabited by the Irish race.

            At the beginning of the present century under the growing influence of the Gaelic League a general reversal of the process began to be perceptible.  Yet even to-day there are scores of Gaelic names with which the prefix is seldom, if ever seen, e.g. Boland, Brophy, Connolly, CORRIGAN, Crowe, Garvey, Hennessy, Kirby, Larkin, to mention a few of the commonest.

            The extent of this resumption can best be illustrated by the mere fact that while in 1890, according to Matheson's calculations, there were twice as many Connells as O'Connells, to-day, (judging by such tests as directories) we have nine O'Connells for every Connell.  I do not know the present proportion of O'Kellys to Kellys, but I am sure it is very much higher than it was in 1890 when the official estimate for all Ireland was 55,900 Kellys and only a mere 400 O'Kellys.

            Now to another class of Mac surnames which is of considerable interest.  This is the assuption by Norman families of surnames of a Gaelic type and the formation under those designations of what practically amount to septs or sub-septs on the Gaelic model.  The majority of these, such as MacSherone ex Prendergast and MacRuddery ex Fitzsimon, are nearly extinct to-day, as are the various offshoots of the Burkes, though no doubt some of their descendants did revert to their original surnames.  Berminghams, however, survive under the name of MacCorish or Corish, Stauntons as MacEvilly, Archdeacons as MacOda or Coady and Nangles as Costello (formerly MacCostello).  Woulfe says that the latter was the first Norman Mac name.  Not all such Norman name assumptions retained a Gaelic form, for d'Exeter, first gaelicized as MacSiurtain, eventually became Jordan (now a common name in the West) and the Jenningses, formerly MacSeoinin, were originally Burkes.

            This practice of forming sub-septs was not confined to Norman families.  Among the offshoots of O'Brien were MacConsidine and MacLysaght.  MacShane stemmed from O'Neill:  in due course this was turned by translation into Johnson and as such is found in that numerous class of concealed Gaelic surnames.  So the name MacShera, now rare, was adopted by some of the Fitzpatricks.  MacSherry (whence the place name Courtmacsherry) on the other hand was a Gaelic patronymic assumed by the English family Hodnett.  MacSherry, it should be noted, is also an indigenous Gaelic surname in Breffny.

            Fitzpatrick, which up to the seventeenth century was MacGilpatrick, is in a class by itself, being the only Fitz name which is Gaelic:  otherwise Fitz (from French fils) always denotes a Norman origin.  It is possible, however, that some of the Fitzhenrys may originally have been MacEnery.

            Unless we adopt an exclusive and doctrinaire attitude we must admit Fitzgerald, Fitzgibbon and Fitzmaurice as Irish.  As I have already remarked many other Norman surnames are among our best-known surnames to-day.  It would be ridiculously pedantic to regard these as anything but Irish.  Not only have they been continuously in Ireland for seven or eight centuries, but they are also not found in England except, or course, when introduced by Irish settlers there.  The Norman name Power, indeed, holds first place for County Waterford.

            One of the most striking and interesting of the phenomena to be observed in study of our subject is the tenacity with which families have continued to dwell for centuries, down to the present day, in the very districts where their names originated.  This obtains in almost every county in Ireland.  Thus, according to Matheson's returns, the births registered for the distinctive Kerry names of Brick, Brosnan, Culloty, Kissane, MacElligot, and MacGillycuddy, to take more or less random examples, are entirely confined to that county.

            In many cases local association has been perpetuated in place names.  Indeed it is a characteristic of Irish place names, particularly those beginning with Bally, Dun, Clon etc., that a large proportion of them are formed from personal names.  Ballymahon, Lettermacaward, Drumconor, Toomevara are a few examples to illustrate this point.  It is dangerous to jump to conclusions and easy to make mistakes in this field:  Thus Kilodonnell in Co. Donegal is the church of O'Toner, not of O'Donnell as would appear at first sight.  Similarly Doonamurray has nothing to do with the surname Murray, being a corruption of Dún na móna; nor has Drumreilly any etymological connexion with the sept of O'Reilly.  Of course the association, especially in the case of the Kil words, is often ecclesiastical rather than genealogical, for many are formed from the names of pre-surname saints and hermits, and so have no interest for the student of surnames.  Those place names beginning with Bally and other Irish words were almost all formed before the seventeenth century and too often when a family was thus distinguished it has ceased to exist or has almost died out in the immediate neighbourhood of the particular townland so designated, but in many cases they are still numerous there.  Nearly all such are gaelic or Hiberno-Norman family names.  There are, however, some exceptions such as Ballybunion and Ballyviniter, which are formed from the English surnames Bunyan and Viniter.

            After the 1602 débâcle, as we must regard the battle of Kinsale, place names with the prefix Castle and Mount or the suffix Town and Bridge like Castlepollard and Crookstown, and occasionally a combination of both like Castletownconyers, began to be used.  For the most part these names honoured planter families, with whom must be classed renegade Gaels who forsook their own people and religion and backed the winning side-or at least the then winning side, for the tables are turned now; though where they represent translations from older Irish place names, as in the case of O'Brien's Bridge and Castledermot, this of course does not apply.  This aspect of our subject can be dismissed without further examination:  it can be studied by anyone interested in it by a perusal of a map or gazeteer, or better still the Index of Townlands, Parishes etc. officially published in connexion with the decennial censuses of the nineteenth century.

            Of more interest to us here is the converse, i.e. those surnames which were actually formed from places.  In England they constitute one of the most numerous classes; in Ireland they are comparatively rare:  so much so indeed that all of them that I know can be enumerated here.  Apart from Anglo-Irish names taken from places in England like Sutton, Preston etc., the only Irish place names so used I have met are Ardagh, Athy, Bray, Corbally, Finglas, Galbally, Kilcash, Rath, Santry, Slane, and Trim, some of which are very rare.  Dease (and Deasy), Desmond, Lynagh, Meade, and Minnagh, formed from extensive territories, may also perhaps be included.  Not all place names found as surnames can be accepted in this category.  Cavan for example is not taken from the town but is a synonym of Keevane or occasionally an abbreviation of Kavanagh; Navan is Mac Cnaimhin, Limerick is O'Luimbric, Kilkenny is Mac Giolla Choinnigh and Ormonde is found in County Waterford oddly enough as a corruption of O'Ruaidh.  The most numerous of these in Ireland to-day is Galway or Galwey.  It does, it is true, derive from a place, but the place is Galloway in Scotland.

            Deasy, mentioned above, might be placed in the class which we may call descriptive.  It indicates "a native of the Decies", as Lynagh means "a Lfeinsterman", Moynagh "a Munsterman" and Meade (with its earlier form Miagh) "a Meathman".  These have a topographical significance, as have Spain, Switzer, Wallace, Brett, London.  Quite a number of descriptive surnames, which at some period must have superseded a normal family surname, are formed from adjectives such as Bane (white), Begg (small), Crone (brown), Creagh (branchy), Duff (black), Gall (foreign), Glass (green), Lawder (strong), Reagh (brindled).

            Phair or Fair is also one of these, but it has been subjected to translation, being the Irish adjective fionn.

            Akin to adjectives are names in the genitive case, of which a few are found among genuine Irish surnames, e.g. Glenny (sometimes Glenn) for a' ghleana and Maghery for an mhachaire.  Here also the process has in some cases been carried a stage further, an chnuic becoming Hill and an mhuilinn Mills; but when met to-day Hill and Mills are more likely to be of English origin.

            Everyone knows the old rhyme which ends with the lines "And if he lack both O and Mac no Irishman is he".  Like most general statements this is not wholly true for, disregarding the undoubted claims of the Burkes, Fitzgeralds etc., we must admit Creagh, Deasy, Crone, Maghery, and the other descriptive surnames as genuinely Gaelic.  Indeed two of the best known and essentially Irish names, Kavanagh and Kinsella, have neither O nor Mac, for they are of the descriptive type.

            Both of these, however sometimes have an O tacked on to them erroneously.  There are some curious instances of this error.  A'Preith (meaning "of the cattle spoil") is well known in County Down for generations under the anglicized form of O'Prey.  Gorham was formerly credited with an O in Co. Galway.  DeHorseys became O'Horseys before ever the influence of the Gaelic League revival brought bogus O's and Macs into being.  Two of the most remarkable, not say ridiculous, of these mistakes are to be found in Limerick city and county where Mackessy (in Irish O' Macasa and recte O'Mackessy in English) appears as McKessy; and Odell, a purely English name, as O'Dell.

            In this connexion, I should refer to those Mac names which through long usage in the spoken language have become O's.  The best known of these are O'Growney and O'Gorman.

            We have already noticed instances of the sub-division of the great septs and the consequent formation in the middle ages of new surnames like MacConsidine.  This arose for various reasons, not the least of which was the desirability of readily distinguishing between a number of people of the same name.  For a similar reason a system of nomenclature exists to-day, particularly in the western counties, whereby the father's christian name is added to a man's legal name.  Thus in Clare, where there may well be several Patrick O'Briens in a single townland, they are known as Patrick O'Brien John, Patrick O'Brien Michael and so on.  This is not merely a colloquial convenience, for these designations are used in ordinary business transactions such as completing an order form or supplying milk to a creamery, and they appear very frequently in the official voter's lists.

            A similar practice, very much in vogue in Limerick in the seventeenth century, has misled some writers funfamiliar with Irish conditiions.  The normal method was to add the father's name, as in the example given above, but with the prefix Fitz.  Thus, to take a well known Limerick surname, John Arthur son of Stephen Arthur was almost invariably described as John Arthur FitzStephen, so that to the uninitiated the man's surname appears to be FitzStephen.

            There are many examples in the sixteenth and seventeenth century records of persons whose names as set down therein are a veritable genealogy.  John MacMahon MacWilliam MacOwen MacShane was, of course, John MacMahon whose father's christian name was William and his great grandfather's was Shane.  Ignorance of this practice on the part of the enumerators probably accounts for the extraordinary number of MacShanes and MacTeiges returned as surnames in such records as the 1659 census all over the country.  According to this there were large numbers of MacWilliams, MacEdmunds, MacDavids, MacRichards etc., and in the same way Fitzjames (sometimes alias Mac James) appears as a common surname.  The prevalence, according to these returning officers, of Oge as a surname bears out this assumption.  Similarly Bane is given as a common surname, though there is little doubt that it was in fact, like Oge, merely an epithet.  Bane does exist as a modern surname; Oge, however, does not, though it may have occasionally survived by translation, as Young.  The Ormond Deeds, especially those of the sixteenth century, contain a great many names formed by prefixing Mac to a christian name.  Besides those mentioned above, MacNicholas, MacPhelim, MacRory, MacThomas, and MacWalter are of most frequent occurence.  Of all these names the only two to be found in any considerable numbers as surnames to-day are MacShane and MacTigue, as it is now spelt.  The latter has in some places been shorn of its Mac and is written Tighe.

            In this connexion it must not be forgotten that a not inconsiderable number of people in the lower stratum of society did not use hereditary surnames even as late as 1650.  In examining family documents I have met with cases of this:  a witness signs himself James MacThomas, whom we know to be the son of Thomas MacTeige--or more probably being illiterate he makes his mark beside the name.  Nevertheless it can safely be stated that the great majority even of the labouring class did have hereditary Mac and O surnames at least from the middle of the sixteenth century.  By the eighteenth, of course, the cottier and small farmer class had come to include a considerable proportion of the old Gaelic aristocracy.

(Source:  Irish Families (CS 498 M3 fol.ref))

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Chapter 3

What is Heraldry
The Origins of Heraldry
The Coat of Arms
Office of the Chief Harold
Blazon of Arms
Corrigan Coat of Arms
Armorial Grant
Ancient Armorial Bearings
Prefix Mac and O’
Irish Clans and Chieftanship