House of O'Brien

• Coat of Arms
• 

  House of O'Brien
  Dál gCais
  Kings and Princes of Thomond
  Ancient arms

• 

  House of O'Brien
  Arms awarded in 1543 after submission to Henry VIII of England

• 

  House of O'Brien
  Barons Ibrickane
  Earls of Thomond

• Dál gCais Branches
• 

  House of O'Grady
  Lords of Cinel Dunghaile and Kilballyowen
  Viscounts Guillamore

• 

  House of O'Kennedy
  Lords of Ormond
  High Chiefs of Ormond Upper and Ormond Lower

• 

  House of MacMahon
  Lords of Corcabaskin
  Marquess of Eguilly and Dukes of Magenta

• Cadet Branches
• 

  House O'Brien of Inchiquin
  Barons Inchiquin and Thomond
  Barons O'Brien of Burren
  Earls of Inchiquin
  Marquesses of Thomond
  Chiefs of O'Brien
  Issued from Murrough O'Brien, 1st Earl of Thomond and 1st Baron Inchiquin, younger son of Turlough O'Brien, King of Thomond

• 

  House O'Brien of Leaghmenagh
  Lords of Leamaneh Castle and Dromoland Castle
  Baronets of Leaghmenagh
  Barons Inchiquin
  Issued from Donough O'Brien, younger son of Murrough O'Brien, 1st Earl of Thomond and 1st Baron Inchiquin

• 

  House O'Brien of Clare
  Barons Moyarta
  Viscounts Clare
  Titular Earls of Thomond
  Issued from Daniel O'Brien, younger son of Connor O'Brien, 3rd Earl of Thomond
  Used undifferentiated arms of the family

• Personal Arms
• 

  Turlogh O'Brien
  Lord of Ibrickane
  Son of Connor O'Brien, King of Thomond from his 2nd marriage
  Uncle of Donough O'Brien, 2nd Earl of Thomond