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Murrough O'Brien, 1st Earl of Thomond

Murrough O'Brien, 1st Earl of Thomond.
The last King of Thomond.
See wikipedia and genealogics.
He mar Eleanor Fitzgerald [dau of Sir Thomas Fitzgerald, Knight of Glin].
He succ his brother as King of Thomond 1540.
In 1543 he surrendered his Irish royalty to Henry VIII and was created 1st Earl of Thomond and 1st Baron of Inchiquin. The creation stated that (unusually) the heir of the Earldom would be his nephew and the heir of the Barony would be his son. He had to abandon his Irish titles, pledge allegiance to the English crown, and convert to the Anglican Church.
He died 7 Nov 1551, bur Ennis Abbey.
Succeeded as Earl of Thomond by his nephew.
Succeeded as Baron of Inchiquin by his son.
He and Eleanor had issue:

Dermod O'Brien, 2nd Baron of Inchiquin.
He mar pre-1550 to his cousin's dau Margaret O'Brien [descendant of Brian Boru and of Edward I].
He succ as Baron 1551.
He died 1557, bur Ennis Abbey.
2nd Baron and Margaret had issue:

Murrough O'Brien, 3rd Baron of Inchiquin.
Said to be born 1550, but see below.
He was murdered in 1573 or 1574.
3rd Baron and Margaret had issue:

Murrough O'Brien, 4th Baron of Inchiquin.
Said to be age 11 at father's death (born 1562 or 1563). Either this or father's date of birth must be wrong.
He mar Mabel Nugent [born post-1575, descendant of Edward III].
His marriage is often confused with his father's marriage. But Mabel Nugent was born after his father's death.
[Complete Peerage] has the correct marriages.
4th Baron was killed in battle, 29 July 1597.
He was buried at Donegal Abbey.
4th Baron and Mabel had issue:

1. Dermod O'Brien, 5th Baron of Inchiquin.

Inchiquin Castle, on Inchiquin Lough, Co.Clare, on 1887 to 1913 map.
See modern satellite view.

An extract of the lament "The Ruin that befell the Great Families of Erin" (c.1720) by the Gaelic poet Aodhagán Ó Rathaille.
From page 11 of [Dineen and O'Donoghue, 1911].
"And sooth to say, the O'Briens have long since become English."

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References

• INCHIQUIN in [Complete Peerage]. 2nd edn, vol.7, p.50.
• INCHIQUIN in [Burkes Peerage]

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Sources yet to be consulted

• THOMOND in [Complete Peerage]

• 1st Earl of Thomond in [DNB]
• 1st Earl of Thomond in [DIB]
• Inchiquin papers. Collection List 143 in [NLI Ms] RR.
• The Inchiquin Manuscripts, John Ainsworth, 1961.

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• Earls of Thomond
• Baron Inchiquin

• The Barons Inchiquin from the 13th Baron Inchiquin onwards (succ 1855) descend from a younger son of the 1st Baron Inchiquin (1st Earl of Thomond).

• Landed Estates project:
  • O'Brien, Earl of Thomond
  • O'Brien, Baron of Inchiquin (and here)