Their genealogies claim that they are kindred with the Eóganachta (themselves led by the O'Sullivans and MacCarthys), descended paternally from Ailill Aulom.
The mountain land extended from the Laghanagerah (Lochan na gCaorach) to Polle Dowa (Poll Dubh in Roscomroe) and then in a south easterly direction to the Slieve Bloom Mountains, which are the limits between Ely O'Carroll and Upper Ossory meeting at a village called Garryvoe or Scully's land.
[4] Of Gaelic Irish descent, the Carrolls have their origins in the ancient kingdom of Éile,[5] commonly anglicized Ely, as a branch of the ruling O'Carroll family.
According to historian C. Thomas Cairney, the O'Carrolls were one of the chiefly families of the Eile who in turn were from the Dumnonii or Laigin who were the third wave of Celts to settle in Ireland during the first century BC.
Historic Ely O'Carroll surnames are: Carroll, Bohan/Bowen, Dooley, Meagher/Maher/Mahar/Mahan, Kelly/Kealy, Flanagan, Corcoran, Healy, Nevin, O'Connor.
Clan Cian was also known as the Cianachta, the Race of Cian, the youngest son of Olioll Ollum King of Munster and grandson of King Eoghan Mor the 1st (known as) Mogh Nuadath of Leith Mogha (Mogha’s Half) of southern Ireland, of the Milesian race of Heber, who contested for supremacy of all Ireland in the second century of the Christian Era.
The Cianachta were led for over 1500 years by a recognized king, prince, high chief, or ruling lord chosen from members of the O’Carroll-Carroll and rival houses of the noble septs of Éile.
The Kingdom of Éile (Ely) was located anciently in Ormond in the Counties Tipperary, Waterford and extending into Offaly, Leix, and Kilkenny.
?as his personal clan for all Cianachta whose families originally lived within the regions ruled by The O'Carroll of Éile O'Carroll in Ireland as well as to all people who wish to honor their background and the ideals that Clan Cian promotes - Irish culture in all its manifestations and the exploration of expatriate Irish's roots back to Ireland.
Teige, the eldest son of this Kean, was a distinguished warrior, who by killing in battle his three rivals, procured for Cormac Mac Art, King of Ulster, the Monarchy of Ireland.
The tenth in descent from him was Teige or Thatheus O'Cearbhuill Boy, King of Éile, who caused the Box of Dimma to be gilt, died about the middle of the 12th century and was succeeded by his son.
In 1548 Teige Caoch O'Carroll, son of Ferdinando, called by Sir James Ware, petty King of Ely, routed the English out of his country, but afterwards submitted and was created Baron of Ely in 1532 (I have not been able to find the record of this patent) which he did not long enjoy, having been slain by his own Sept headed by his own kinsman and competitor Cahir O'Carroll, who was afterwards slain by William Adhar O'Carroll, younger brother of Teige, who was knighted 30 March 1567 and made Governor of Ely and Captain of his Nation by Sir Henry Sidney, Lord Justice of Ireland.
Sir Mulrooney O'Carroll, son of Sir William, was knighted by Sir George Carew, L. D. of Ireland, at Dublin Castle, St. James's Day, 1 March 1603, being the day of the Coronation of King James I. Roger O'Carroll, son and heir of Sir Mulrooney, was ousted out of his estates by Cromwell, he having attached himself to the King's party under the Duke of Ormond, but his eldest son and heir, Charles O'Carroll, was in great favour with Kings Charles II and James the I, who were not able to restore him to his paternal estate; the latter made him grants of large tracts of land on the Monoccasy River in the Province of Maryland in the North America, which was divided into three manors of 20,000 acres (81 km2) each and called after the possession he had lost in Ireland, viz., Ely O'Carroll and Doughoregan.
This gentleman was also made Attorney General of the Province and his estates are still in the possession of his grandson, Charles O'Carroll of Carrolston, Esq.
He married O'Kennedy's daughter and had thirty sons, whom he formed into a troop of horse and presented to Duke of Ormond for the service of King Charles I.
He was afterwards, through the interest of the Duke of Ormond, made a Lieutenant-Colonel in the British Service by Queen Anne, in which he rose to the rank of Lt. General, obtained permission to bear the Insignia of the Order of St. Iago in England, had also the style of Sir Daniel and was Colonel of a Regiment of Horse.
Three other O'Carrolls, John, Donagh and Kedagh, obtained grants of land in Connaught from King Charles II in compensation for their losses in Leinster.
Specifically in the case of Munster, The Great Book of Irish Genealogies compiled between 1645 – 66 by Dubhaltach Mac Fhirbhisigh and edited more recently by Nollaig Ó Muraíle (2003), in Vol.
The Cianachta were recognized as a racial group in ancient Ireland and now called again to assemble as a clan in these modern times.
In addition to these individuals, the Mitchell family of Maryland claim descent from the aforementioned Charles Carroll of Carrollton through the line of their founding matriarch Lillie Mae Carroll Jackson who, in addition to being a descendant of his, is revered today as one of the earliest and most prominent of the leaders of the civil rights movement.
Most famous is Doughoregan Manor,[9] which remains a family seat in the possession of descendants of Charles Carroll of Carrollton, who is buried there.