Clann Cosgraigh

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Clann Cosgraigh or Clann Coscraig{{Cite book|last=Duffy|first=Seán|title=Mediaeval Ireland: An Encyclopaedia|publisher=Routledge|year=2005|isbn=0-415-94052-4|location=London, New York|pages=485-6}} was a branch of the Uí Briúin Seóla and also the name of the district on the eastern side of Lough Corrib, County Galway which they inhabited and ruled prior to the Norman invasion.

The eponym of the lineage was Coscrach Mór mac Duinn, who died in the Battle of Dún Ganiba in 799.{{cite book |title=Annals of Ulster |pages=799.1}} Its chiefs were the Meic Áeda (now rendered McHugh or McGagh, via Mac Aodha), who, like the Muintir Murchada, claimed descent from Cenn Fáelad mac Colgan, King of Connacht.{{cite book |last1=O'Flaherty |first1=Roderic |title=A Chorographical Description of West or H-Iar Connaught |date=1684 |publisher=Irish Archaeological Society |location=Dublin |page=6 |edition=1846}}{{cite book |last1=MacFirbis |first1=Dubhaltach |title=Leabhar Mór na nGenealach |pages=201.6-202.1}} Early generations of the lineage competed with the Muintir Murchada and Uí Fiachrach Aidhne for the kingship of South Connacht.