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 O'Brien (priest)
John O'Brien (30 May 1931 – 6 January 2008) was a Roman Catholic priest who worked in the Archdiocese of Dublin from 1956 until his death in 2008. He is best remembered as one of Ireland's leading conductors, a prominent organist and founder of the retired St. James' Choir and the Glasnevin Musical Society.