Daniel O'Brien, 1st Viscount Clare

Daniel was born about 1577, the third and youngest son of Connor O'Brien and his second wife, Una O'Brien.[1] His father was the 3rd Earl of Thomond. His father and his mother were from different branches of the O'Briens, an important Gaelic Irish dynasty that descended from Brian Boru, medieval high king of Ireland.[2]

On 1 July 1604 in Leixlip, county Kildare, O'Brien was knighted and became Sir Daniel O'Brien. He was elected as one of the two "knights of the shire", as county MPs were then called,[6] for Clare County in the Irish House of Commons 1613 to 1614.[7] In the Irish Parliament of 1634–1635 he replaced his nephew Barnabas O'Brien, the future 6th Earl of Thomond, who had absented himself to England.[8]

Sir Daniel married Catherine FitzGerald, daughter of Gerald FitzGerald, 14th Earl of Desmond and his second wife, Eleanor Butler.

Daniel and Catherine had four sons:

1. Donogh (died 1638), married Elizabeth Dowdall but died in 1638 predeceasing his father.[9]
2. Connor, succeeded as 2nd Viscount Clare
3. Morrough
4. Teige

—and a daughter:

1. Margaret

Sir Daniel was a member of the Supreme Council of the Catholic Confederates. On 27 June 1652, at Ross Castle near Killarney, Sir Daniel together with Lord Muskerry surrendered to Ludlow. Sir Daniel served as hostage to guarantee Muskerry's compliance with the terms.[10]

At the Restoration O'Brien returned to Ireland and recovered a good deal of his estate. On 11 July 1662 Charles II created him Viscount Clare.[11] Lord Clare, as he now was, died in 1666 and was succeeded by his eldest surviving son Conor.[12]

• Pollard, Albert Frederick (1895). "O'Brien, Daniel, first Viscount Clare (1577?–1663)". In Lee, Sidney (ed.). Dictionary of National Biography. 41. New York: MacMillan and Co. pp. 310–311. OCLC 8544105.