Letters patent issued on Fri 19th Oct 1714
To Henry O'Brien
A peerage of the Kingdom of Great Britain , during the reign of George I
Previously known as Earl of Thomond in the Peerage of the Kingdom of Ireland.
Ordinality on date: 9
Previous of title: true
- Viscount Tadcaster
C 231/9, p. 319; 1 Geo. I, pt. 12 (C 66/3509) no. 21