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.
Vincent O'Brien (composer)
Vincent O'Brien (9 May 1871 – 21 June 1948), Irish organist, music teacher and composer. O'Brien was an important figure in early 20th-century Irish music. For some, he is mainly known as the first teacher of singers such as John McCormack, Margaret Burke-Sheridan and the writer James Joyce.