Cas or Tál Cas was the eponymous ancestor and dynastic founder of the Dál gCaisIrish pedigrees; or, The origin and stem of the Irish nation, John O'Hart, 1892, page 155, https://archive.org/details/irishpedigreesor_01ohar/page/154 (Deisi Tuaiscirt) clan in Gaelic Ireland, from whom all branches of the Dalcassian dynasty claim common descent.
Life Tál Cas was the son of Conall Eachluath and his wife Coirpthe, daughter of Eochaid Mugmedon.Bart Jaski, 'The (legendary) rise of Dál Cais', in: Seán Duffy (ed.), Medieval Dublin XVI: proceedings of Clontarf 1014–2014: national conference marking the millennium of the Battle of Clontarf (Dublin, 2017). 15–61. He acquired the nickname Tál (meaning "adze") as he was the foster son of a wright. He became King of Thomond and made a gavel of his territory among his thirteen sons. On his death the kingship of Thomond passed to his eldest son Blait.Tadhg Ó Donnchadha,"An Leabhar Muimhneach", 1900, page 86, page 237, page 295, https://archive.org/details/leabharmuimhneac01odon/page/86/mode/2up, https://archive.org/details/leabharmuimhneac01odon/page/236/mode/2up, https://archive.org/details/leabharmuimhneac01odon/page/294/mode/2upPedigrees of the MacNamara Family, R.W Twigge, published 1908, republished by Martin Breen 2006, page 12
Family
He had thirteen sons, at least three of whom would found substantial lineages whose descendants would rule as lords over substantial territories: Blod (Uí Bhloid) Carthann Fionn Oenghus (Uí Óengussa) Uí Ronghaile Uí Chearnaigh Eochaidh Bailldearg Uí Floinn Uí Thoirdhealbhach Ua Briain Ua Cinnéidigh Ua hEachthighearn Caisín (Ua Caisin) Eochaidh Cinéal nDúnghaile Sineall Uí Dhobharchon Carthann Clan Cuiléin Eoghan mac Cuiléin Clan Cuiléin Uachtarach Maol Cluiche mac Cuiléin Mac Conmara Ua hAllmharain Ua hArtagain Aonghus Ceann-nathrach Cinéal Fermaic Ua Deághaidh Cinéal gCuallachtaigh Ó Gríobhtha Cinéal mBaoi Aonghus Ceann-aitinn Clann Ifeamain Clann Neachtain Lughaidh/Dealbhaoth na Dealbhna Muinnter Chochláin Carthann Dal gCais Leithe Lachtmhuighe Aedh Ui Aedha Lughaidh Éile Muinnter Dhobharchon Muinnter Chonraoi Muinnter Chearnaigh Muinnter Aonghusa Muinnter Dhubhthaigh Séadna Cormac Caindeach Nae Loisceann
Genealogy Surnames purported to be of Dalcassian origin have a statistically significant correlation with the possession of the Y-DNA signature R-L226 and thus this mutation is believed to be associated with their ancestral founder.
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