William Mo'r De Burgh

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William Mo'r De Burgh

Death: 1270
Athankis, Ireland
Immediate Family:

Son of Richard Mór de Burgh, 1st Baron of Connaught and Hodierna de Gernon
Husband of Frances Delamond, of Norfolk
Father of William Liath Oughter De Burgh, Sir and Sir William Liath de Burgh, Justiciar of Ireland
Half brother of Margery de Burgh; Alice Burgh; Richard De Burgh; daughter of Richard de Burgh; Matilda de Burgh and 1 other

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About William Mo'r De Burgh


William Og was ancestor to the Earl's of Clanricarde, the Mac William Iochtar, The Bourkes of Mayo, and after the extinction of the de Burgh creation of the Earldom of Ulster, the de Burgh line.

Sir William Og de Burgh

had one son:

Sir William the grey/ Liath de Burgh, d.1324

Sir William the grey, in turn, had three sons:-

--Sir Edmond Albanach de Burgh, 1st Mac William Iochtar/ Lord of the Lower Mac William, d.1375.

--John de Burgh (1350-1398) Theologian, Chancellor of the University of Cambridge

--Sir Ulick de Burgh, Lord of Clanricarde (d.1352) 2nd Mac William Iochtar. Ancestor of the Earls of Clanricarde.

Sir William Óg de Burgh, Anglo-Irish noble and soldier, died 1270.

Sir William Óg was the third son of Richard Mor de Burgh, Lord of Connacht. De Burgh served with distinction in France with King Henry III in 1245 and later in Scotland. He was involved in fierce feudal warfare in Ireland where he killed the Lord of Desmond. He was killed at the Battle of Áth an Chip or Athankip by the Ua Conchobair Kings of Connacht, in 1270.[1]

He was survived by at least one son, Sir William Liath de Burgh, Custos or Warden of Ireland, who married Una, a daughter of the Mac Jordan of Connacht, and died in 1324. William Óg was thus ancestor the Mac William Iochtar, the Bourkes of County Mayo.