John O'Brien explained
John O'Brien may refer to:
Public officials
American
- John O'Brien (Ohio politician) (1932–1985), former member of the Ohio House of Representatives
- John D. O'Brien, state senator in the 1997–1998 Massachusetts legislature
- John F. O'Brien (secretary of state) (c. 1850–1927), Secretary of State of New York, 1903–1906
- John F. O'Brien (judge) (1874–1939), New York Court of Appeals judge
- John H. O'Brien, 4th Fire Commissioner of the City of New York
- John J. O'Brien (civil servant) (1919–2001), investigated the assassination of President John F. Kennedy
- John J. O'Brien (commissioner), former commissioner of the Massachusetts Probation Service
- John P. O'Brien (1873–1951), 98th mayor of New York City
- John L. O'Brien (1911–2007), American politician in the Washington House of Representatives
Irish
British
Canadian
New Zealand
Australian
Sportspeople
Baseball
Footballers
Other sports
- John O'Brien (basketball, born 1888) (1888–1967), American basketball referee and executive
- John O'Brien (basketball, born 1916) (1916–1994), American professional basketball player in the 1940s
- John O'Brien (boxer) (1937–1979), Scottish boxer of the 1960s and '70s
- John O'Brien (cricketer, born 1961), English cricketer
- John O'Brien (Irish cricketer) (1866–1920), Irish cricketer
- John O'Brien (hurler) (born 1982), Irish hurler
- John O'Brien (rower) (1927–1995), New Zealand representative rower
- John 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