Niall Noígíallach, Niall of the Nine Hostages may be mythological.
The Ui Neill were descended from Niall Noigiallach (better known as Niall of the Nine Hostages) who, as his name indicates, was a powerful enough king to have held one hostage each from the five provinces of Ireland and one each from the Britons, the Franks, the Saxons, and the Scots.
Birth Year Estimation
Based on his father's birth year + 25 years he would be born around 350, however this would make him over 100 at his death, so his birth is adjusted to 360, but there still would appear to be a missing generation here.
He is the legendary progenitor of the Uı́ Néill dynasties, a warlord who reigned in the late 4th century and early 5th century. Niall Mor, Niall of the Nine Hostages is listed as the 126th monarch of Ireland in John O'Hart's Roll of the Monarchs of Ireland
While primary sources for Niall Noigiallach do not exist (Wikipedia), the Y-chromosome lineage of the medieval Uí Néill dynasty is one of the world's three most profilic (Calloway, 2015). Moore (2006) states that:
"Figures such as Niall of the Nine Hostages reside at the cusp of mythology and history, but our results do seem to confirm the existence of a single early-medieval progenitor to the most powerful and enduring Irish dynasty. They also lend support to the veracity and remarkable knowledge preservation of the genealogical and oral traditions of Gaelic Ireland and give a powerful and specific illustration of the link between prolificacy and power in one European society within the past 2 millennia".
the children of Inne, the daughter of Lugaid
- Faichu - ancestor of the Cenél Fiachach: the Southern Uí Néill
↑ Calloway, E. (2015, January 23). Genghis Khan's genetic legacy has competition. Nature. NPG. Retrieved from www.nature.com
↑ Moore, L. T., McEvoy, B., Cape, E., Simms, K. & Bradley, D. G. (2006). A Y-chromosome signature of hegemony in Gaelic Ireland. The American Journal of Human Genetics, 78(2), pp. 334–338. dx.doi.org/10.1086/500055. PDF
Albert F. Schmuhl, The royal line : chart prepared for the New York Stake Genealogical Board, Church of Jesus Christ of Latter-day Saints centennial exhibition, March, 1936 (Salt Lake City: self published, 1929) https://familysearch.org/search/catalog/239856?availability=Family%20History%20Library. (http://familysearch.com : accessed 7 June 2015). Revised 1980. Purports to go back to Adam, "Genealogical lineages shown on the chart may not always be from father to son, especially in the reigning houses of Kings; some ancient connections are based on legends, believed to be true."
It may be possible to confirm family relationships with Niall Noigiallach by comparing test results with other carriers of his Y-chromosome or his mother's mitochondrial DNA.
Y-chromosome DNA test-takers in his direct paternal line on WikiTree: