Dál gCais
gaelic Irish tribe
Dál gCais ([ˌd̪ˠaːlˠ ˈɡaʃ], sometimes known as the Dalcassians) are a Gaelic Irish clan, generally accepted by contemporary scholarship as being a branch of the Déisi Muman, that became very powerful in Ireland during the 10th century. Their genealogies claimed descent from Tál Cas. Their known ancestors are the subject of The Expulsion of the Déisi tale and one branch of their blood-line went on to rule the petty kingdom of Dyfed in Wales during the 4th century; probably in alliance with the Roman Emperor Magnus Maximus.
Brian Boru is perhaps the best-known king from the dynasty and was responsible to a significant degree for carving out their fortunes. The family had built a power base on the banks of the River Shannon and Brian's brother Mahon became their first King of Munster, taking the throne from the rival Eóganachta. This influence was greatly extended under Brian who became High King of Ireland, following a series of wars against Hiberno-Norse kingdoms and the Chiefs of other Irish clans, before dying famously at the Battle of Clontarf in 1014. Following this the Dál gCais provided three more High Kings of Ireland; Donnchad mac Briain, Toirdelbach Ua Briain and Muirchertach Ua Briain.
From the 12th–16th centuries, the Dál gCais contented themselves with being reduced to the Kingdom of Thomond. They attempted to claim the Kingdom of Desmond for a time, but ultimately the MacCarthys held it. The Kennedys also held the Kingdom of Ormond for a time.
“Dál gCais” enters the record as gaelic Irish tribe. Crown Archives preserves that source wording while asking what gCais, gaelic and Irish can confirm, complicate or overturn.
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This entry incorporates text from “Dál gCais” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.