The first three sons became the ancestors of three Irish dynasties, known as the Teóra Connachta, or the Three Connachta of the province of Connacht.
Niall founded the numerous O' Neill dynasties of Ulster and Meath.
See that the territories of the northern and southern Ui Neill as well as the Teora Connachta all meet at Sligo. It is highly probable that it is from this region they first set out on their conquests.
For example M222 (R1b1b2a1a2f2) is tied to the Uí Neill and the Uí Briúin and the Uí Fiachra which are both branches of the ancient Connachta (supposedly descended from the half brothers Niall,Brion and Fiachra).
Satem -- Sanskrit, OCS, Lithuanian, and Armenian -- vs Centum -- Greek, Latin, OIR, Gothic, and Hittite;
|Brian from who descended the Uí Briúin,|
Ui Brian Seola
|Fiachra Tir Fhiacrach|
Ailill Tir Olliol
Niall of the Nine Hostages had eight sons, Loegaire, Conal Crimthan, Fiach, Maine, Conal Gulban, Owen, Cairbre, and Ennius the first four remained in Connacht and North Leinster, where their descendants were called the Southern Ui-Neill; the second four went north, becoming the Northern Ui Neill.
The Sons of Niall Naoighiallach
|Loegaire Mac Neill (died c. 462)|
Patrick is said to have met Lóegaire's daughters near Cruachan, a complex of prehistoric sites associated with the kingship of Connacht in legend and in history, also Lóeguire,
His dealings with the saint were believed to account for his descendants' lack of importance in later times. There are several accounts of his death, all of which contain supernatural elements, some of which concern his wars against Leinster.
O' Connellan, O' Quinlan
Conall Gulban Mac Neill (died c. 464)
|Fiach Mac Neill flourished 507–514) King of Mide|
Fiachu appears as a conqueror of Meath in the annals.
The O'Higgins sept which produced filí or poets, including the famous Sligo poet Tadg Dall O' Huiginn, is said to be descended from his son Uigin.
O' Molloy, Mac Geoghegan, O' Brennan
| Eoghan Mac Neill|
Eoghan mac Néill (died 465) son of Niall Noígiallach, was an Irish king who founded the kingdom of Ailech, later Tír Eoghain (modern County Tyrone) in the 5th century. He was also the ancestor of the Cenél nEoghain dynasty and their septs (MacLaughlin, O'Neill, Corrigan, etc.).
Eogan was a close friend of Saint Patrick and received Patricks blessing. With his brother the high king Lóegaire mac Néill (d.462), he was one of the judges in a dispute over the succession to Amalgaid (d.440), king of Connacht among his sons competing to rule their territory of Tir Amalgaidh in northwest Connacht.
Eoghan, King of Tír Eoghain, and Prince of Inis Eoghain is buried at St. Patrick's Church in Iskaheen, Innishowen, Donegal. A plaque there states "Eoghan Prince of Iniseoghain, Son of Niall of the Nine Hostages. Died 465 of grief for his brother Conall. Baptised by Patrick and buried in Uisce Chaoin"
His sons included Muiredach mac Eógain, his successor in Ailech; Fergus, founder of the Cenél Fergusa; and Echach Binnich, founder of the Cenél mBinnig.
| Cairbre Mac Neill (fl. c. 485–493) Cairbre|
This territory in north Sligo is named after Cairbre mac Neil, High King of Ireland, reputed enemy of St. Patrick.
Coirpre may have led some of the earliest recorded Uí Néill conquests in the midlands.In earlier historical times, Cenél Coirpri may have been of sufficient importance to attract the attention of largely hostile writers. Tirechán's life of Patrick states that Coirpre was cursed by the saint, at Tailtiu, so that none of his descendants would be High King
It was a saor tuath or free territory.
O'Connors Sligo were Lords since the 13th century. They are a branch of the O'Conchobar dynasty related to the Kings of Connacht.
| Maine Mac Neill|
Siol Maine Fir Tethba
O 'Kearney (Fox)
|Tir Fhiacrach Tireragh|
the country of Fiacra, half brother of Niall of the Nine Hostages
the ODowds Ua Dubhda were lords,
the chief families are Ui Fiacrach
|Tir Olliol Tirirrel|
the country of Aillil the half brother of Niall of the Nine Hostages.
Mac Donnchada Mac Donagh Lords of Tir Olliol and Corran from the 13th century.
Cormac na Beag Fada is ancestor of this family they are a younger branch of the Mac Diarmada of Magh Luirg.
Named from the ancient tribe the Luighne
O'Haras Ua hEaghra were lords.
This tuath was Aiteach Tuath, an unfree tuath, as it was ruled by a dynasty unrelated to the the ruling aristocracy of Connacht.
|An Corrán Corran|
the O'Garas, O' Gadhra were lords
were ousted by the Mac Donnchadha
These sons are the eponymous ancestors of the various Uí Néill dynasties: Eógan of the Cenél nEógain and Conall Gulban of the Cenél Conaill, making up the northern Uí Néill; Fiachu of the Cenél Fiachach dynasty, Lóegaire (the king who Saint Patrick is said to have converted) of the Cenél Lóegaire, Maine of the Uí Maine, Eógan of the Cenél nEógain, Conall Gulban of the Cenél Conaill, Conall Cremthainne of the Clann Cholmáin and the Síl nÁedo Sláine, and Coirpre of the Cenél Coirpri, making up the southern Uí Néill.
The term Síol denotes the seed, or descendants, of Muiredach.
Branches of the Síol Muireadaigh included
Conmaicne Rein na bFomorach
A contact of tribute to the King of Connacht states that
“Twelve score good cloaks, two hundred cows without error, six score swine, a firm demand due from the Conmaicne”
And in return
“The righteous king of Conmaicne is entitled to ten horns on entering his drinking chamber, ten swift horses to mount, two bracelets, and two sets of chess.”
The Síol Muireadaigh were a dynasty of related clans, all descendants of King Muiredach Muillethan of Connacht (died 702), all of whom lived in north-central Connaught. The term Síol denotes the seed, or descendants, of Muiredach.
Septs of the Síol Muireadaigh included