Henry O'Brien, 5th Earl of Thomond
Irish earl
About Henry O'Brien, 5th Earl of Thomond
Lived 1588 – 1639 (aged 50–51).
Henry O'Brien, 5th Earl of Thomond PC (Ire) (1588–1639), styled Lord Ibrickane until 1624, was summoned to the House of Lords of the Irish Parliament of 1613–1615.
Birth and origins
Henry was born the eldest son of Donogh O'Brien and Elizabeth FitzGerald. His father was the 4th Earl of Thomond. His father's family were the O'Briens, an important Gaelic Irish dynasty, that descended from Brian Boru, medieval high king of Ireland.
Henry's mother was the fourth daughter of Gerald FitzGerald, 11th Earl of Kildare and his wife Mabel Brown.
Marriage and children On 13 July 1608 O'Brien married Mary Brereton, a rich heiress, the only daughter of William Brereton, 1st Baron Brereton and Margaret Savage.
Henry and Mary had five daughters: Lady Mary (died 1686) married, on 24 June 1627, Charles Cokayne, 1st Viscount Cullen Lady Margaret, who married first Edward Somerset, 2nd Marquess of Worcester and secondly Donough Kearney Lady Elisabeth (1616–1659) married, on 21 August 1636, Dutton Gerard, 3rd Baron Gerard (1613–1640), grandson of Thomas Gerard, 1st Baron Gerard Lady Anne (died 1645) married, in 1641, Henry O'Brien, 7th Earl of Thomond Lady Honora married first Sir Francis Inglefield, knight of Wotton-Bassett, and secondly Sir Robert Howard, son of the Earl of Berkshire
House of Lords O'Brien was summoned on 3 March 1613 as Lord Ibrickane to the Irish House of Lords of the Irish Parliament of 1613–1615, the only parliament of King James I in Ireland.
5th Earl Ibrickane succeeded his father on 5 September 1624 as the 5th Earl of Thomond.
Death Thomond died in 1639 and was buried in St Mary's Cathedral, Limerick. He had no son and was succeeded in his titles by his brother Barnabas O'Brien, 6th Earl of Thomond.
Notes and references
Don’t just read it —
keep it.
Full-length biographies made to live with: read them, listen on the way to work, watch them tonight.
- E-book
- Audio
- Video
Instant download · yours to keep · every purchase keeps this site free
Important facts
Family & relationships
People in Henry O'Brien, 5th Earl of Thomond's life
Named in this biography and alive at the same time
Contemporaries
People whose lives overlapped Henry O'Brien, 5th Earl of Thomond's
Frequently asked questions
Who was Henry O'Brien, 5th Earl of Thomond?
Irish earl
When was Henry O'Brien, 5th Earl of Thomond born?
Henry O'Brien, 5th Earl of Thomond was born in 1588.
When did Henry O'Brien, 5th Earl of Thomond die?
Henry O'Brien, 5th Earl of Thomond died on 26 July 1639.
What nationality was Henry O'Brien, 5th Earl of Thomond?
Henry O'Brien, 5th Earl of Thomond's recorded nationality: Kingdom of Ireland.
Sources & further reading
· Wikipedia: Henry O'Brien, 5th Earl of Thomond
· DBpedia: Henry O'Brien, 5th Earl of Thomond
Cite this page
APA: Biography.guide. (2026). Henry O'Brien, 5th Earl of Thomond. https://biography.guide/henry-o-brien-5th-earl-of-thomond/
MLA: "Henry O'Brien, 5th Earl of Thomond." Biography.guide, https://biography.guide/henry-o-brien-5th-earl-of-thomond/.
Chicago: "Henry O'Brien, 5th Earl of Thomond." Biography.guide. https://biography.guide/henry-o-brien-5th-earl-of-thomond/.
Data last updated: 2026-09-28 · Spot an error? Report a correction.
Portrait: Wikimedia Commons · author & licence
Page generated 2026-10-05 04:08 UTC