Donn mac Cumasgach was a king of

Maigh Seóla Maigh Seóla (), also known as Hy Briuin Seola, was the territory that included land along the east shore of Lough Corrib in County Galway, Ireland. It was bounded to the east by the Uí Maine vassal kingdom of Soghain and extended roughly fr ...

who died in 752. He may be the earliest recorded ruler of Maigh Seóla, as he is referred to as ''King of the

Uí Briúin The Uí Briúin were a royal dynasty of Connacht. Their eponymous apical ancestor was Brión, son of Eochaid Mugmedon and Mongfind, and an elder half brother of Niall of the Nine Hostages. They formed part of the Connachta, along with the U ...

of the South'' in the annals' obit. In the

Leabhar na nGenealach ''Leabhar na nGenealach'' ("Book of Genealogies") is a massive genealogical collection written mainly in the years 1649 to 1650, at the college-house of St. Nicholas' Collegiate Church, Galway, by Dubhaltach MacFhirbhisigh. He continued to add m ...

, he is stated to be the great-grandson of

Cenn Fáelad mac Colgan Cenn Fáelad mac Colgan (died 682) was a King of Connacht from the Uí Briúin branch of the Connachta. He was of the branch which developed into the Uí Briúin Seóla, who were centred on Tuam in modern County Galway. He is the first member of ...

and the father of Coscrach Mór, the eponym of the

Clann Cosgraigh Clann Cosgraigh or Clann Coscraig was a branch of the Uí Briúin Seóla dynasty 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. Its chiefs wer ...

. The Annals of Ulster place his killing ''sub anno'' 757, but do not name his killer. The king-list of Maigh Seóla is difficult to reassemble due to its royal line's sporadic annalistic appearances. However, Connmhach Mór mac Coscraigh—apparently Donn's grandson through the Coscrach Mór mac Duinn in the Leabhar na nGenealach line—is the next king of the region mentioned in the annals. Connmhach appears as the victor at the Battle of Drung in 836 and in his obit is described as "King of Uí Briúin", though he was himself also king of Hy Briuin Seola.

References

* ''West or H-Iar Connaught''

Ruaidhrí Ó Flaithbheartaigh Roderick O'Flaherty ( ga, Ruaidhrí Ó Flaithbheartaigh; 1629–1718 or 1716) was an Irish historian. Biography He was born in County Galway and inherited Moycullen Castle and estate. O'Flaherty was the last ''de jure'' Lord of Iar Connacht, a ...

, 1684 (published 1846, ed.

James Hardiman James Hardiman (1782–1855), also known as Séamus Ó hArgadáin, was a librarian at Queen's College, Galway. Hardiman is best remembered for his '' History of the Town and County of Galway'' (1820) and '' Irish Minstrelsy'' (1831), one of the f ...

). * ''Origin of the Surname O'Flaherty'', Anthony Matthews, Dublin, 1968, p. 40. * ''Irish Kings and High-Kings'', Francis John Byrne (2001), Dublin: Four Courts Press, * ''Annals of Ulster'' a
CELT: Corpus of Electronic Texts
a
University College Cork
* ''Annals of Tigernach'' a

a
University College Cork
of McCarthy's synchronisms at

Trinity College Dublin , name_Latin = Collegium Sanctae et Individuae Trinitatis Reginae Elizabethae juxta Dublin , motto = ''Perpetuis futuris temporibus duraturam'' (Latin) , motto_lang = la , motto_English = It will last i ...

. * Byrne, Francis John (2001), Irish Kings and High-Kings, Dublin: Four Courts Press, {{DEFAULTSORT:Donn mac Cumasgach People from County Galway 752 deaths 8th-century Irish monarchs Year of birth unknown