One in five men in Donegal are descendants of Niall of the Nine Hostages, the Irish High King who according to legend brought St Patrick to Ireland as a slave, a genetic study has found.
The study, by scientists in Trinity College Dublin, discovered that as many as one in twelve Irish men could be descended from the fifth century warlord who was head of the most powerful dynasty in ancient Ireland. But in the northwest, the number rises to 21%.
PhD student Laoise Moore at the Smurfit Institute of Genetics at Trinity made the discovery when she tested the Y chromosome of over 800 men from across Ireland. The chromosome is passed down from father to son.
Professor Dan Bradley, who supervised the research, said the results reminded the team of a similar study in central Asia, where scientists found eight percent of men with an identical Y chromosome. Further studies found they shared the same chromosome as the dynasty linked to Genghis Khan.
‘It made us wonder if there could be some sort of Genghis Khan effect in Ireland and the best candidate for it was Niall,’ Bradley said. They calculated that the most recent common ancestor lived about 1700 years ago. Combined with the strong concentration of the gene in the northwest, this pointed to the Ua Niall dynasty.
The team then checked with genealogical experts who gave them a list of people with surnames that are genealogically linked to the Ua Niall dynasty, the descendants of Niall. The results showed these people had the same chromosome, proving a link between them and Niall’s descendants.
‘Before I would have said that characters like Niall were almost mythological, like King Arthur, but this actually puts flesh on the bones,’ Bradley said.
Among Niall Noígiallach’s sons were Conall, Eoghan and Enda. These would in turn become ‘the Northern Ua Niall’. After his death, Niall’s kingdom was divided between them into Tír Chonaill, Tír Eoghan and Tír Enda (roughly equivalent to the modern counties of Donegal, Tyrone and Derry).
The Southern Ua Niall claim descent from Niall’s other sons: Coirpre, Loegaire, Fiachu, Maine and Conal Cremthainne. Between them, the various Ua Niall dynasties would at their peak control half of Ireland, called Leth Conn (Conn’s Half).
It is not known exactly how many sons and daughters Niall sired. The first three (Northern Ua Niall) seem pretty secure, since they’re mentioned in some of the earliest Irish writings which survive. According to his bigrapher Adomnán, Colm Cille is a great-great-grandson of Niall, descended from Conal Gulban. Adomnán (himself a nephew of Colm Cille) was writing in the late 600s, around 100 years after his famous uncle died. This places him 200 years or so removed from Niall Noígiallach, who modern historians calculate died around 450.
Over time, as the Ua Niall dynasties consolidated their power and repeatedly pressed their claim for the kingship of Tara, it became politically important to be a descendant of Niall. Irish kings and their genealogists therefore ‘discovered’ new sons of Niall, and with it their own claims to the high kingship of Ireland. For instance, its doubtful if Maine son of Niall ever existed. One Irish historian called the inclusion of the Uí Maine among the Ua Niall ‘a polite fiction.’
The Ua Niall dynasties are sometimes confused with modern O’Neills, but they in fact are a much larger group. There were no surnames in Niall’s day, and the O’Neills (part of the Cenel Eoghan of Tír Eoghan) took their surname from Niall Glundubh, a high king who died in 917. The first person to use the surname was his grandson, Domhnall Ó Niall. The O’Donnells are descended from Domhnall, a king of the Cenel Conaill who died in 901.
Among the septs tracing or claiming descent from Niall are the following: Ó Domhnaill (O’Donnell), Mac Domhnaill (McDonnell, McDonald), Ó Niall (O’Neill), Mac Niall (McNeill), Ó Luinigh (Lunny, Loony), Ó Dubhagáin (Doogan, Dougan, Dugan), Ó Conchobhair (O’Connor), Mac Lochlainn (McLoughlin, McLoughlan), Ó Gallchobhair (Gallagher), Ó Dochartaigh (Doherty, Docherty, Ó Canann (Cannon), Ó Catháin (Kane, Cain, Caine), Ó Flaithbheartaigh (Flaherty, Laverty), Ó hÁdhmaill (Hamill), Ó Cearbhalláin (Carolan, Carlin), Ó Baoighill (Boyle), Mac Suibhne (Sweeney, Swiney), and Ó Brolcháin (Bradley).