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.
John William Alexander O'Brien
Major General John William Alexander O'Brien, (13 June 1908 – 27 May 1980) was a senior officer in the Australian Army during the Second World War. He was awarded the Distinguished Service Order for his service as commander of the 2/5th Field Regiment during the Syria–Lebanon Campaign. As Deputy Master General of the Ordnance he was involved in the development of the short 25-pounder and the Owen Gun. After the war he was the Australian supply and defence production representative in Washington, DC from 1951 to 1954, and the Mayor of Woollahra from 1971 to 1972 and 1975 to 1976.