William O'Brien
William O'Brien (2 October 1852 – 25 February 1928) was an Irish nationalist, journalist, agrarian agitator, social revolutionary, politician, party leader, newspaper publisher, author and Member of Parliament (MP) in the House of Commons of the United Kingdom of Great Britain and Ireland. He was particularly associated with the campaigns for land reform in Ireland during the late 19th and early 20th centuries as well as his conciliatory approach to attaining Irish Home Rule.
William O'Brien, 4th Earl of Inchiquin
On 29 March 1720, he married his cousin, Lady Anne Hamilton, the eldest daughter and heiress of George Hamilton, 1st Earl of Orkney, and his wife Elizabeth (née Villiers). His wife became 2nd Countess of Orkney in her own right in 1737. They had five children:He married, secondly, Mary Moore, daughter of Stephen Moore, 1st Viscount Mount Cashell and Alicia Colville, on 12 October 1761