Agastache

John de Burgh (English: /dˈbɜːr/; d’-BER; 1286 – 18 June 1313) was an Irish noble who was the son of Richard Óg de Burgh, 2nd Earl of Ulster and his wife, Margarite.

Heir apparent to the Earldom of Ulster, he married (as her first husband) in Waltham Abbey, Essex, on 30 September 1308, Elizabeth de Clare, sister of Gilbert de Clare, 7th Earl of Hertford and 8th Earl of Gloucester. She was the founder of Clare College, Cambridge, and a granddaughter of King Edward I of England. Gloucester in turn married John's sister Maud.

John and Elizabeth had one son:

• William Donn de Burgh, 3rd Earl of Ulster (1312–1333)

However, John died in Galway the next year, leaving his infant son William heir to the Earldom.

• House of Burgh, an Anglo-Norman and Hiberno-Norman dynasty founded in 1193
• Lord of Connaught

• Burke, Bernard (1884). The General Armory of England, Scotland, Ireland, and Wales; comprising a registry of armorial bearings from the earliest to the present time. London: Harrison & Sons.
• Moody, T. W.; Martin, F. X.; Byrne, F. J., eds. (1989). A New History of Ireland: IX: Maps, Genealogies, Lists, A Companion to Irish History, Part II. Oxford: Oxford University Press. ISBN 978-0-19-959306-4.
  • Earls of Ulster and Lords of Connacht, 1205–1460 (de Burgh, de Lacy and Mortimer), p. 170.