The O'Brien Baronetcy, of Leaghmenagh in the County of Clare, was created in the Baronetage of Ireland on 9 November 1686; for more information see Baron Inchiquin.
He was a merchant, Lord Mayor of Dublin and Liberal Member of Parliament for Cashel.
The second Baronet represented King's County in the House of Commons as a Liberal for over thirty years.
The O'Brien Baronetcy was created in the Baronetage of the United Kingdom on 15 January 1916; for more information see Baron Shandon.
[1] The heir presumptive after the presumed-only holder is the other patrilineal grandson of the 6th Baronet, James Patrick O'Brien (born 1964).