Ireland has had nobles or peers for over a millennium. They fall into a number of categories.

  1. Ancient Irish Gaelic nobles (pre-English rule)
  2. Peers of the Lordship of Ireland and the Kingdom of Ireland (created between 1171 and 1800)
  3. Peers of the United Kingdom of Great Britain and Ireland

This list covers peerages possessed by Irish people from any of the three categories. The title is listed first, followed by famous figures associated with the family beneath. It does not include non-Irish people awarded Irish titles; for example, the Duke of Connaught, son of Queen Victoria.

Gaelic Nobles

Family Seat: Clonalis House.
  • The O'Brien, Prince of Thomond (also known as Lord Inchiquin(1543 Kingdom of Ireland barony))
Family Seat: Dromoland Castle (until twentieth century)
  • The MacCarthy Mór, Prince of Desmond
  • The O'Callaghan
  • The O'Carroll of Ely
  • The O'Donoghue of the Glens
  • The O'Donovan
  • The O'Long
  • The MacGillycuddy of the Reeks
  • The O'Grady
  • The O'Kelly of Gallagh and Tycooly
  • The MacDermot, Prince of Coolavin
  • The Ó Ruairc, Prince of Breifne
  • The O'Neill Mór, Prince of Tyrone and The O'Neill, Prince of Clanaboy
  • The O'Dogherty of Inishowen
  • The O'Donel, Prince of Tirconnell
  • The Maguire, Prince of Fermanagh
  • The MacMorrough Kavanagh, Prince of Leinster
  • The O'Morchoe
  • The Fox

Irish Peerages created by England/Great Britain/United Kingdom

  • The Duke of Leinster, (formerly known as the Earl of Kildare), Ireland's premier peer.
    • Garret (Mór) Fitzgerald - viceroy under King Henry VIII
    • Garret (Óg) Fitzgerald - son of the above and also a viceroy
    • Silken Thomas - son of the above, rebelled against Henry VIII and was executed.
    • Lord Edward Fitzgerald - 18th century rebel associated with 1798 rebellion

Family seats: Carton House, Co. Kildare (until early 20th century) Leinster House, Dublin City (until beginning of the 19th century - now seat of Dáil Éireann
  • The Duke of Abercorn --title created in 1868 for heir male of the Hamilton family
  • The Marquess Conyngham
    • Henry,Lord Mountcharles --son of the 7th Marquess Conyngham, rock impressario and unsuccessful Dáil candidate for Fine Gael in the 1992 Irish general election.

Family Seat: Slane Castle, Co. Meath.

  • Baron Killanin
    • Lord Killanin - head of the International Olympic Committee
    • Michael (Mouse) Morris - successful Irish jockey and horse-trainer.

  • Earl of Longford
    • 6th Earl of Longford - theatre manager in the Gate Theatre in Dublin.
    • Frank Pakenham, 7th Earl of Longford, (brother of the 6th earl) - British politician, author and campaigner.
    • Lady Antonia Fraser, (daughter of Frank Pakenham) historian and author
    • Thomas Pakenham, 8th Earl of Longford - author

Family Seat: Tullynally Castle (formerly called Pakenham Hall), Co. Westmeath.

  • Viscount Powerscourt

Family seats: Powerscourt House, Co. Wicklow (until mid 20th century - house subsequently destroyed by fire); Powerscourt House, Dublin (until 19th century - now a famous shopping arcade)

  • Baron Dunsany
    • Edward John Moreton Drax Plunkett, 18th Baron - author and dramatist
    • St. Oliver Plunkett - martyred Roman Catholic Archbishop of Armagh, canonised by Pope Paul VI in 1976

Family Seat: Dunsany Castle, Co. Meath

  • The Earl of Fingall
    • Countess of Fingall - author of Seventy Years Young
(title extinct 1984...distant kin to the Lords Dunsany)
Family Seat: Killeen Castle, Co. Meath (until mid 20th century. Castle burned by the Provisional IRA in 1981)