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By the latter part of the 10th Century the once mighty Eoghanacht Dynasty was beginning to crumble.  At the same time another dynasty (Dal Cais) was on the rise.  The Dal Cais, a tribal grouping based in the Clare-Limerick area, came under the control of Brian Boru in 976.  Two years later he defeated and killed the Eoghanacht King of Munster and proceeded to wage deadly war against the kingdoms of Connaught, Meath, Leinster, and Breifne.  By 1014 his victory at Clontarf united all of Ireland, nominally at least, under a single leader, though Brian himself was slain.  It was at this time that the Ui Ciarṁaic chieftains came to be subordinated to their new Dalcassian overlords.  The Annals of Ireland, by the Four Masters, has several entries pertaining to Ui Ciarṁaics during this Dalcassian era.


In the year 1087:  “The battle of Rath-Edair (the fort of Edar located on or near the hill of Howth in County Dublin) between the men of Leinster and Munster, where Muircheartach Ua Brian and the men of Munster defeated the Leinstermen and Domhnall, son of Mael-na-mbo and Diarmaid Ua Briain, and Enda, son of Diarmaid; and where a great slaughter was made of the Leinstermen, together with the son of Murchadh Ua Domhaill, lord of Ui-Drona and Conall Ua Ciarmhaic and Ua Neill of Magh-da-chon, etc.”


In the year 1115: “Diarmaid Ua Briain, King of Munster, was taken prisoner by Muicheartach Ua Briain; and Muircheartach Ua Briain assumed his kingdom again and set out with an army into Leinster and Breagha.  Muircheartach Ua Ciarmhaic, lord of Aine; Domhnall Ua Conchobhair Ciarraighe; Murchadh Ua Flainn; the son of Flannchadha, lord of Muscraighe, were slain.  The (great stone church) of Ard Breacain full of people, was burned by the men of Munster and also many other churches in the country of Feara-Breagh.”


In the year 1123:  “A great army was led by Toirdealbhach, son of Ruaidhri Ua Conchobhair, as far as Bealach-Eochaille (Youghal), by which he took all the hostages of Desmond.  The Gaileanga took a house at Daimhliag-Chianin upon Murchadh Ua Maeleachlainn, King of Teamhair; and they burned eighty houses around it and killed many of his people, on that occasion.  Ua Maeleachlainn escaped being killed or burned, by the protection of Cianan.  Domhnall, son of Donnchadh, royal heir of Teamhair, was slain by the Gailenga.  An unusual attack was made upon the successor of Ailbhe, Maelmordha, son of Cloithnia.   A house was forcibly taken from him and the son of Cearbhall Ua Ciarmhaic, lord of Aine, in the middle of Imleach and seven persons were therein killed; but the chiefs escaped through the miracle of God, Ailbhe and the church.  The Bearnan-Ailbhe (St. Silbhe’s gapped or broken bell) was burned on this occasion.  The person who had taken the house, Gillacaech Ua Ciarmhaic (who was after being named a deacon), was killed before the end of the month and his head was cut off, in revenge of the violation of the laws of god and Ailbhe.”


In the year 1162:  “Diarmaid Ua Laighnen, lector of Cluain-Uamha (Cloyne Monastery, County Cork), was killed by the Ui Ciarmhaic.”


It cannot be overlooked that in three of the just mentioned years (1115, 1123 and 1162) churches were involved and some explanation of this is relevant.  It seems that as a result of the Viking wars (9th Century) the respect of the Irish for sacred places was seriously eroded and the annals record numerous raids on churches and monasteries.  Also part of the trouble lay in the organization of the Irish church which was monastic rather than diocesan.  Church positions were frequently held by laymen and in many cases, ecclesiastical positions of power were given to members of the founding family of the monastery, abbot, priory, etc.  This tendency helped to open the way for the later assumption of power in some of the larger monasteries by local ruling families.  These “secular clerics” oftentimes demanded their tithes and spoils from cattle raids.  In this context internecine sept struggles oftentimes took place in connection with rival monastic power disputes.


It has often been said 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 Irish surnames were well established during the reign of Brian Boru and members of the Ui Ciarṁaic sept (plural) came to adopt the hereditary surname Ua Ciarṁaic (singular) to themselves.


It was also during the waning days of Dalcassian rule in Munster (c. 1190) that the “Ua” (singular) and the “Ui” (plural) prefixes came to become “Ó.”  “Ua” and “Ó” actually served the same purpose but one form is older (Ua) and the other form (Ó) is more modern and can be used for both singular and plural name prefixes.  They both mean grandson or even an earlier ancestor and more loosely they mean male descendant.


This “Ó” was not long in usage when another prefix modification took place.  The “Ó” came to become O’ (with an apostrophe) due to a very simple misunderstanding.  An acute accent ( ’ ) called a “fada” is used in the Irish language to accent some vowel sounds.  It was always used in the case of  “Ó” Irish surnames and thus Ó Ciarṁaic came to become “O’ Ciarṁaic.”  In many manuscript works lines of script were closely packed together and there was not sufficient room to put the fada above the capital prefix “Ó.”  So instead the fada was put on the right hand side of the “Ó.” For example Ó Ciarṁaic would become O’ Ciarṁaic.  Those unfamiliar with the Irish language, understandably, mistook the fada for an apostrophe and thus the misunderstanding arose.


Thus, as Dalcassian rule gave way to Norman rule (13th Century) the original Ua Ciarṁaic… later Ó Ciarṁaic… had come to be called by the hereditary surname O’ Ciarṁaic which means the descendant of the Ciarṁac.

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