People — M
Michael O'Brien
b. 1955
politician
Michael O'Brien
b. 1971
politician
Michael O'Byrne
b. 1991
association football player
Michael O'Callaghan
b. 1946
rugby union player
Michael O'Callaghan
Michael O'Carroll
1911 – 2004
theologian
Michael O. Chinda
politician
Michael O'Connell
politician
Michael O'Connell
b. 1962
Australian rules football player
Michael O'Connell
botanist
Michael O'Connor
b. 1965
costume designer
Michael O'Connor
1913 – 2022
Michael O'Connor
b. 1930
Michael O'Connor
b. 1987
association football player
Michael O'Connor
b. 1960
association football player
Michael O'Connor
b. 1998
association football player
Michael O'Connor
b. 1980
baseball player
Michael O'Connor
b. 1996
Canadian football player
Michael O'Connor
1810 – 1872
Catholic priest
Michael O'Connor
1829 – 1883
Catholic priest
Michael O'Connor
1942 – 2025
curate
Michael O'Connor
1856 – 1925
farmer
Michael O'Connor
1865 – 1940
politician
Michael O'Connor
b. 1960
rugby league player
Michael O'Connor
b. 1984
swimmer
Michael O'Connor
1900 – 1957
water polo player
Michael O'Dea
b. 1938
politician
Michael O'Dea
politician
Michael O'Doherty
b. 1901
publisher
Michael O'Donnell
b. 1984
politician
Michael O'Donnell
1928 – 2019
physician
Michael O'Donnell
b. 1968
politician
Michael O'Donnell
rugby league player
Michael O'Donoghue
1940 – 1994
screenwriter
Michael O'Donoghue
b. 1996
association football player
Michael O'Donohue
1835 – 1912
architect
Michael O'Donovan
association football player
Michael O'Dwyer
1887 – 1975
hurler
Michael O. Emerson
b. 1965
religion sociologist
Michael O'Farrell
1864 – 1928
Catholic priest
Michael O'Farrell
1949 – 1989
Gangster
Michael O. Fitzgerald
b. 1949
writer
Michael O'Flaherty
b. 1959
lawyer
Michael O'Flaherty
1891 – 1952
politician
Michael O'Flanagan
1876 – 1942
historian
Michael O. Freeman
b. 1948
politician
Michael O'Gara
Catholic priest
Michael O'Gorman
1874 – 1937
Australian rules football player
Michael O'Gorman
1965 – 2018
coxswain
Michael O'Grady
b. 1942
association football player
Michael O'Grady
1824 – 1876
politician
Michael O'Halloran
b. 1991
association football player
Michael O'Halloran
b. 1997
Michael O'Halloran
b. 1971
hurler
Michael O'Halloran
1933 – 1999
politician
Michael O'Halloran
2000 – 2023
politician
Michael O'Hanlon
b. 1961
writer
Michael O'Hanlon
1890 – 1967
politician
Michael O'Hanrahan
1877 – 1916
revolutionary
Michael O'Hara
b. 1996
athletics competitor
Michael O'Hara
screenwriter
Michael O'Hara
1932 – 2018
volleyball player
Michael O'Hare
b. 1985
television presenter
Michael O'Hare
1952 – 2012
television actor
Michael O'Hearn
b. 2001
alpine skier
Michael O'Hehir
1920 – 1996
hurler
Michael O'Herlihy
1929 – 1997
film director
Michael O'Hickey
1860 – 1916
Michael O'Higgins
economist
Michael O'Higgins
1917 – 2005
politician
Michael O Johnson
b. 1954
business executive
Michael O'Kane
1849 – 1917
Catholic priest
Michael O'Keefe
1932 – 2021
lawyer
Michael O'Keefe
1854 – 1941
politician
Michael O'Keefe
1864 – 1926
politician
Michael O'Keefe
b. 1955
television actor
Michael O'Keeffe
b. 1934
biochemist
Michael O'Keeffe
b. 1990
association football player
Michael O'Kennedy
1936 – 2022
politician
Michael O'Laughlen
1840 – 1867
politician
Michael O'Leary
b. 1961
business executive
Michael O'Leary
b. 1958
actor
Michael O'Leary
1858 – 1930
Michael O'Leary
b. 1950
poet
Michael O'Leary
1936 – 2006
politician
Michael O'Loughlin
b. 1977
Australian rules football player
Michael O'Loughlin
b. 1997
sport cyclist
Michael O'Meara
hurler
Michael O. Moore
b. 1963
politician
Michael O'Moore Creagh
1892 – 1970
military personnel
Michael O'Nan
1943 – 2017
mathematician
Michael O'Neal
b. 1951
politician
Michael O'Neill
b. 1938
economist
Michael O'Neill
b. 1951
actor
Michael O'Neill
b. 1969
association football player
Michael O'Neill
b. 1967
diplomat
Michael O'Neill
1953 – 2018
poet
Michael O'Neill
1909 – 1976
politician
Michael O'Pake
1940 – 2010
politician
Michael O. Rabin
1931 – 2026
computer scientist