The Dal gCais Tribe and Their Clans

Origin of the Dal gCais Clan of Ireland

The name Dal gCais originated from the larger population of Munster Déisí, who were one of several Celtic groups to appear in Ireland around the 5th century. These Deisí, or vassal group, populated the south of ancient Ireland stretching from Waterford to Limerick, and were divided into two separate groups, the Déisí Muman of Waterford and Tipperary and the Deisi Tuisceart of North Munster, who later became the Dal gCais.

The Dal gCais homeland base and royal seat was Thomond which is part of Munster, the ancient province of Ireland. It has been suggested that the Kingdom of Thomond was put in place by the prominent O’Neills to weaken the power of the Eóganachta, whose seat was at Cashel.

Dal gCais means 'peoples or children of Cas', who was a fifth century King of Munster and ancestor of the Dal gCais. They rose to power in the 10th century and produced a number of Kings including the legendary Brian Boru.

In modern times they became known as the Dal gCais or Dalcassian Clan or Sept. A clan is usually a kinship group or group of families. A sept is normally seen as a group of clans and their families who are descended from the same ancestor, in this case, Brian Boru (Bryan Boru) and the O’Briens.

The Dal gCais Grow In Power

However under the leadership of Brian Boru, the Dal gCais became a threat to Tara itself, the seat of the High King of Ireland, when they united with the Eóganachta against Ivar the Norse ruler of Limerick, after which their fortune and power grew.

But it was the rise of the Dál gCais at the expense of the Eóganachta that would set in motion a train of events that would eventually see Brian Boru become the legendary High King of Ireland.

The Dalcassian army stood by Brian Boru's side at the Battle of Clontarf. Among those of the Dalcassians who where involved in the Battle in 1014 were The O'Briens, Kennedys, Quinns and and McGraths.

Dal gCais, Dalcassian, Clans of Ireland

To Find Your Clan See Below our list of Clans of the Dal gCais.........

Origin of the Aherne Clan Name

Origin of the Aherne Clan Name

The name is an anglicised form of the gaelic Ó hEachthighearna meaning descendant of Eachthighearna (person name meaning lord of horses). They are said to descend from Echtiern who was the brother of Brian Boru, the High King of Ireland.The name originated in the Home land of the Dál gCáis in County Clare and so has always been associated with the area....read more

Origin of the Barron Clan Name

Origin of the Barron Clan Name

In Ireland, they are thought to be descended from Sir Art MacBaron O’Neill, a natural son of Matthew O’Neill, the first Baron of Dungannon. Matthew, originally called Ferdoragh, died at the hand of his grandson Shane O’Neill the Proud who was against Anglo-Irish law and its titles. This title began in the 1540s and was bestowed on all first sons of the Earls of Tyrone until they assumed the title themselves....read more

Origin of the Boland Clan of Name

Origin of the Boland Clan of Name

Boland comes from the gaelic form Ó Beólláin which was formed from a Norse Viking name. The name was originally portrayed with the O’ and was spelt as Bolan, since then the prefix has been dropped and the d added to the end, making the name Boland. They originated in the counties of Clare and Sligo where they held a family seat in ancient times but are widespread through Ireland....read more

Origin of the Casey Clan Name

Origin of the Casey Clan Name

In ancient times, O’Casey came from the gaelic, O’Cathasaigh word meaning watchful or Vigilant in War. The O’Caseys were descendants of the O’Carrolls, the Princes of Ely. The Princes of Ely were in turn descended from the Kings of Munster. The Ó Cathasaigh ascended into at least five distinct septs. Most of them originated in County Cork and County Limerick although they are also found in the counties of Cork, Dublin, Fermanagh, Mayo and Louth / Monaghan areas. In medieval times the most prominent Caseys came from the Dublin and Fermanagh areas. The name is still numerous in all of these Counties today. ...read more

Origin of the Clancy Clan Name

Origin of the Clancy Clan Name

The name Clancy is derived from the gaelic name Mac Fhlannchadh from the personal name Flannchadh which means (flann meaning red-haired man), so the carriers of the name would have been sons of a red haired man. The name Clancy was originally spelt MacClancy, they had a reputation for being in the “thick of fighting”. It’s not surprising that the name translates to the “son of the red warrior”....read more

Origin of the Clohessy Clan Name

Origin of the Clohessy Clan Name

The name Clohessy stems from the gaelic O’Clochasaigh which is derived from the Irish word Cloch, meaning stone. When the name is has the prefix as O, this means “son of” or” male descendant of” but the name lost this prefix in the 17th century. They originated from County Limerick and County Clare, the area of Ballycloghessy is named after the family. They are still dominant in these areas today and are also found in Cork and Tipperary....read more

Origin of the Considine Clan Name

Origin of the Considine Clan Name

The name Considine originally appeared as MacConsidine and in gaelic as Mac Consaidin, which means son of Constantine. The name Considine was borne by a branch of the O’Brien’s from County Clare in the province of Munster. Many bearers of the name are still found today in the counties of Clare and Limerick today. One of the earliest recordings of the name in Ireland was an early Bishop of Killaloe, Consaidin O’Briain (1164-1194). He was the youngest son of Toirdelbach O’Briain, King of Thomond who was a direct descendant of the last Great High King of Ireland, Brian Boru....read more

Origin of the Coughlan Clan Name

Origin of the Coughlan Clan Name

This surname originates from the Anglicisation of 2 distinct Gaelic sept names: Mac Cochlain and O’Cochlain, where Cochlain was a personal name which meant ‘hooded-one or one wearing a cloak’. Personal names often derived from some identifying feature and this was another example. Surnames then used prefixes to signify their descendants. Here mac means son of and ó (Ua) means grandson or more generally descendants of…. These 2 lines can be traced to 2 separate locations; MacCochlain to County Offaly and the barony of Garry castle and they also had many strongholds in the Banagher- Clonmacnoise area. ...read more

Origin of the Downey Clan Name

Origin of the Downey Clan Name

The name Downey originates from the irish spelling O’Dunadhaigh. Dun meaning fort, keeper of the fort. The name Downey with different spellings, Downie and Duny. It was two possible origins, the first being from the old irish O Dunaghaigh, the O meaning male descendant of.The other comes from O Maoldhomhraigh, which means descendant of the servant of the church. This was anglicised Muldowney but later when on the become Downey....read more

Origin of the Heffernan Clan Name

Origin of the Heffernan Clan Name

The name is derived from the Gaelic name Ó Heifearnain, meaning demon.Their original territory was of the O’Heffernan sept was Corofin in County Clare, County Limerick and County Tipperary. Heffernans are still primarily found in these areas today....read more

Origin of the Hogan Clan Name

Origin of the Hogan Clan Name

The original form in Gaelic of the name Hogan is Ó hÓgáin, meaning descendant of Ógán, derived from the irish word óg, meaning young or young warrior. The origin of the name was Ógán from who the family claim descent, he lived in the 10th Century and was an uncle of the Great Brian Boru, the last great high King of Ireland who defeated in the Vikings in the battle of Clontarf in 1014....read more

Origin of the Hurley Clan Name

Origin of the Hurley Clan Name

The Hurley name has become the English version of at least 3 distinct original names. The first being Ó hUirthile who were part of the Dál gCais tribe based in Clare, the second being the Ó Muirthile based around Kilbritian west Cork and the third being Ó hlarlatha from the district of Ballyvourney also from Cork. Hurley is also the known as Cammane, the Irish name for a Hurley (stick) or Caman used in the traditional Irish sport. An interesting example of the translation of surnames is found in County Clare where some of whom who were originally name Hurley are now known as Commane....read more

Origin of the Kennedy Clan Name

Origin of the Kennedy Clan Name

Kennedy is an anglicised form of the gaelic name Ó Ceannéidigh, descendant of Ceannéidigh, which was a personal name derived from ceann (which means head) and éiigh( which means ugly). Cinneide was the name of the nephew of Brian Boru (Bryan Boru), High King of Ireland so the name has a direct link to the ancestory line of Brian Boru....read more

Origin of the MacMahon Clan Name

Origin of the MacMahon Clan Name

The name McMahon is an anglicised from of the Irish name Mac Mathghamhna which means “bear or good calf”. Later on the name became MacMathuna. The surname arose separately in two distinct areas, County Clare and County Monaghan. In the former, the Mac Mahon’s originated from the counties of Clare and Limerick in Munster and were part of the Dál gCais Tribe. They descend from Brian Boru through his grandson. Mahons son was the first the carry the name MacMahon, which means Son of Mahon....read more

Origin of the MacNamara Clan Name

Origin of the MacNamara Clan Name

The name MacNamara comes from the Irish Mac Conmara which means” son of the hound of the sea” before being translated into English from McNamara. The MacNamara clan are proud descendants of Cu Mara their 10th Century ancestor of the Dal gCais.The Macnamara’s were second only to the great O’Briens in the Dál gCais tribe. Therefore they were hereditary Marshalls to the O’Brien’s....read more

Origin of the McGrath Clan Name

Origin of the McGrath Clan Name

The McGraths came from County Clare where they held a famous seat and then onto County Waterford, they were known as poets. The first recorded name of the McGrath was John McGraith who was an Arthur dating back to 1391....read more

Origin of the O'Brien Clan Name

Origin of the O'Brien Clan Name

The O’Brien family are directly descended from Brian Boru (Bryan Boru). The name Ua Briain (grandson of Brian) was adopted by his great-grandson Muirchetach when he became High-King of Ireland in 1101, in honour of him. The chief of the Dalcassian Council today is Conor Myles O’Brien, Prince of Thomond. The O’Briens are one of the Great historic Irish families and their heartlands were in Thomond.They became earls of Thomond and Inchiquin. They were famed as soldiers the most famed being Brian Boru....read more

Origin of the O'Curry Clan Name

Origin of the O'Curry Clan Name

The name is derived from the Irish word curraigh meaning “wet plain or march”. The Irish meaning of the name is Ó Camhraí or Ó Comraige meaning descendant of Comhraidhe (spear). The name originally in old Irish was O’Corra or O Corraigh. In Ulster the Name Corry or Ó Corry is a well-known alternative for Corr. The O’Curry name is scattered throughout Ireland and so has multiple origins....read more

Origin of the O'Grady Clan Name

Origin of the O'Grady Clan Name

The O’Grady name is one of the most memorable of the Dalcassian clans and is today still closely connected with County Clare. The name is derived from the Irish form Ó Gráda, descendand of Gráda, which means noble. The Seat and chief of the name was at County Limerick in Killballyowen....read more

Origin of the O'Hanrahan Clan Name

Origin of the O'Hanrahan Clan Name

The O’Hanrahan name was originally spelled Ó hAnnracháin, which may be a variation of the word O hAnradhain, which is derived from ánragh meaning soldier (the descendant of the warrior). The name was originally used in the kingdom of Leinster where kings and nobles ruled and existed in ancient pre 10th century Ireland. Many of the Ó hAnnracháin’s who emigrated from our shores changed their name to Hanrahan where they are very common in the United States....read more

Origin of the O'Mahony Clan Name

Origin of the O'Mahony Clan Name

O’Mahony is a gaelic form of the name Ó Mathghamhna, meaning descendant of Mathghamhain (Good Calf). O’Mahony’s they take their name from the Forefather of the great Mahoney Clan, Mathghamhain who was the son of Cian and Sadhbh (who was the daughter of the great Brian Boru)....read more

Origin of the Quinn Clan Name

Origin of the Quinn Clan Name

Quinn or Quin is an anglicised form of the gaelic O Cuinn, meaning “son of Conn”. The O’Cuinnde notes ancestry from Conn of the Hundred Battles, a legendary High King of Ireland. The word Conn is derived from the gaelic work Ceann (meaning head) implying a person of intellectual ability....read more

Origin of the Twomey Clan Name

Origin of the Twomey Clan Name

The irish for the word Twomey is O Tuama, descendant of Tuama. It could be derived from the word Tuaim meaning Hill. When used with the “O”, is denotes to be “descendant of”. This old family name was descended from Tuaim Snama, who was an eight century king of Osraigi, who was apparently of Dalcassian origin. They were descended from Brian Boru’s bother Mahon (Mathghamhain) who was King of Munster before the reign of Brian. He was killed by the Vikings alongside the Eoghanachta. The Twomey’s were first found in County Cork although they did descend from the Dál gCais in the North of Munster. ...read more

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