O'Brien (tennis) (born 1932), Australian tennis player and hostage in the 2014 Sydney hostage crisis John O'Brien (water polo) (1931–2020), Australian Olympic water polo player John Ambrose O'Brien (1885–1968), founding owner of the Montreal Canadiens ice hockey team John O'Brien (businessman), British businessman Other people John O'Brien (marine artist) (1831–1891), Canadian marine artist John O'Brien, the original name of stage actor John T. Raymond (1836–1887) John O'Brien (poet) (1878–1952), Australian priest, poet and author John B. O'Brien (1884–1936), American actor and director John O'Brien (publisher), Irish American publisher and academic John O'Brien (novelist) (1960–1994), American author John O'Brien (filmmaker) (born 1962), Vermont film director John O'Brien (advocate), disability inclusion advocate and writer John O'Brien (screenwriter), screenwriter of Fireflies and K-9 John Roger O'Brien (1903–1982), birth name of Jack O'Brien (jazz pianist) See also Jack O'Brien (disambiguation) Sean O'Brien (disambiguation)