Namesakes
Australian Prime Ministers:
1 prime minister
John McEwen (a.k.a. Jack) 1967-1968 
Emmy Award Winners:
3 actors
(actor) Jack Benny 1959 The Jack Benny Show
(actor) Jack Klugman 1963; 1971; 1973 The Defenders; The Odd Couple
(actor) Jack Albertson 1976 Chico and the Man
Fictional Characters from Books:
4 characters, 2 heroes
Jack Dawkins 1838 Oliver Twist
Jack Aubrey 1969 Master and Commander
Jack Torrance 1977 The Shining
Jack Ryan 1984 The Hunt for Red October
Jack Frost 1984 Frost at Christmas
Bloody Jack 2002 Bloody Jack
Fictional Characters from Movies:
6 characters
Jack Torrance 1980 The Shining
Jack Skellington 1993 The Nightmare Before Christmas
Jack O'Neill 1994 Stargate
Jack Powell 1996 Jack
Jack Dawson 1997 Titanic
Jack Sparrow 2003 Pirates of the Caribbean
Fictional Characters from Plays and Musicals:
2 characters, 1 hero
Captain Jack Absolute 1775 The Rivals
John Worthing (a.k.a. Jack) 1895 The Importance of Being Earnest
Saucy Jack De 'Ath 1995 Saucy Jack and the Space Vixens
Fictional Characters from Song Titles:
12 characters
(character) Jack 1961 Hit the Road Jack
(character) Jack 1966 Happy Jack
(character) Jack Flash 1968 Jumpin' Jack Flash
(character) Jack 1973 Captain Jack
(character) Jack 1977 Jack-in-the-Green
(character) Jack 1978 Nice Man Jack
(character) Jack 1982 Jack & Diane
(character) Jack 1996 The House Jack Built
(character) Jack 1999 Crazy Jack
(character) Jack 2002 Mr. Jack
(character) Jack 2009 The Ballad of Jack and Haley
(character) Jack 2013 Ramblin' Jack
Fictional Characters from Television:
34 characters, 1 hero
Jack Deveraux 1965 Days of Our Lives
JJ Deveraux (a.k.a. Jack) 1965 Days of Our Lives
Jack Jones 1968 Dad's Army
Jack Tripper 1977 Three's Company
Jack Ewing 1978 Dallas
Jack W. Tweeg 1986 The Adventures of Teddy Ruxpin
Jack Arnold 1988 The Wonder Years
Jack "J. D." Darius 1989 Baywatch
Jack McCoy 1990 Law & Order
Jack Maddox 1991 The House of Eliott
Jack Frost 1992 A Touch of Frost
Jack Stewart 1993 Diagnosis: Murder
Jack Geller 1994 Friends
Jack Huey 1994 Due South
Jack Tran 1994 Heartbreak High
Jack Hodgson 1996 Silent Witness
Jack Richmond 1996 Suddenly Susan
Jack O'Neill 1997 Stargate SG-1
Jack Gallo 1997 Just Shoot Me!
Jack Berger 1998 Sex and the City
Jack McFarland 1998 Will & Grace
Jack McPhee 1998 Dawson's Creek
Jack Mannion 2000 The District
Jack Bristow 2001 Alias
Jack Hudson 2002 Sue Thomas: F.B.Eye
Jack Malone 2002 Without a Trace
Jack Sloane 2003 NCIS
Jack Shephard 2004 Lost
Jack Chase 2005 Close to Home
Jack Hodgins 2005 Bones
Jack Harkness 1963; 2006 Doctor Who; Torchwood
Jack Donaghy 2006 30 Rock
Jack Hunter 1993; 2014 Boy Meets World; Girl Meets World
Jack Bauer 2001; 2014 24; 24: Live Another Day
Jack Johnson 2014; 2019 Black-ish; Mixed-ish
Fictional Characters from Traditional Tales:
4 characters, 1 hero
Jack English
Jack English
Jack Frost English
Little Jack Horner English
Jack Sprat English
Hall-of-Famers:
7 ice hockey, 5 football, 3 baseball, 3 basketball
(baseball) Jack Chesbro 1946
(ice hockey) Jack Adams 1959
(ice hockey) Jack Walker 1960
(ice hockey) Jack Laviolette 1962
(ice hockey) Jack Ruttan 1962
(ice hockey) Jack Darragh 1962
(basketball) Jack McCracken 1962
(baseball) Jackie Robinson 1962
(ice hockey) "Black" Jack Stewart 1964
(ice hockey) Jack Marshall 1965
(football) Jack Christiansen 1970
(basketball) Jack Twyman 1982
(football) Jack Ham 1988
(football) Jack Lambert 1990
(football) Jack Youngblood 2001
(football) Jack Butler 2012
(baseball) Jack Morris 2018
(basketball) Jack Sikma 2019
Irish Presidents and Prime Ministers:
1 prime minister
(prime minister) Jack Lynch 1966-1973; 1977-1979
Most Valuable Players:
2 winners
Jackie Robinson 1949 baseball
Jackie Jensen 1958 baseball
New Zealand Prime Ministers:
1 prime minister
Jack Marshall 1972
Nobel Prize Winners:
2 physics, 1 medicine
(physics) Jack Steinberger 1988
(physics) Jack Kilby 2000
(medicine) Jack W. Szostak 2009
Notable Activists and Revolutionaries:
1 activist
(activist) Jack Kevorkian 1928-2011
Notable Actors and Entertainers:
16 actors, 1 comedian/actor, 1 reality star
Jack Hoxie 1885-1965
Jack Benny 1894-1974
Jack Albertson 1907-1981
Jock Mahoney (a.k.a. Jack) 1919-1989
Jack Palance 1919-2006
Jack Warden 1920-2006
Jack Elam 1920-2003
Rodney Dangerfield (a.k.a. Jack) 1921-2004
Alvy Moore (a.k.a. Jack) 1921-1997
Jack Klugman 1922-2012
Jack Lemmon 1925-2001
Jack Nicholson 1937-
Jack Shepherd 1940-
Jack Scalia 1950-
Jack Black 1969-
Jack Osbourne 1985-
Jack Reynor 1992-
Jack Dylan Grazer 2003-
Notable Artists:
1 cartoonist
Jack Kirby 1917-1994
Notable Athletes:
3 ice hockey, 2 baseball, 2 basketball, 2 boxing, 1 driving, 1 golf, 1 rugby, 1 soccer, 1 tennis
(boxing) Jack Johnson 1878-1946
(ice hockey) Jack Laviolette 1879-1960
(ice hockey) Jack Darragh 1890-1924
(ice hockey) Jack Adams 1894-1968
(boxing) Jack Dempsey 1895-1983
(baseball) Jackie Robinson 1919-1972
(driving) Jack Brabham 1926-2014
(basketball) Jack Twyman 1934-2012
(golf) Jack Nicklaus 1940-
(baseball) Jack Morris 1955-
(basketball) Jack Sikma 1955-
(soccer) Jack Wilshere 1992-
(tennis) Jack Sock 1992-
(rugby) Jack Nowell 1993-
Notable Businesspeople:
5 businesspersons
Jack Daniel 1849-1911
Jack L. Warner 1892-1978
Jack Tramiel 1928-2012
Jack Ma 1964-
Jack Dorsey 1976-
Notable Evildoers:
2 murderers, 1 pirate
"Calico" Jack Rackham 1682-1720
Jack the Ripper ?-18xx
Jack Ruby 1911-1967
Notable Filmmakers:
2 directors
Nicolas Roeg (a.k.a. Jack) 1928-2018
Jack Hill 1933-
Notable Journalists:
1 journalist
(journalist) John Reed (a.k.a. Jack) 1887-1920
Notable Musicians:
2 musicians, 1 singer
Eddie Fisher (a.k.a. Jack) 1928-2010
Jackie Wilson 1934-1984
Jack White 1975-
Notable Scientists and Inventors:
1 engineer, 1 paleontologist
Jack Kilby 1923-2005
Jack Horner 1946-
Notable Writers:
4 authors, 1 poet
Jack London 1876-1916
John Reed (a.k.a. Jack) 1887-1920
Jack Kerouac 1922-1969
Jack Higgins 1929-2022
Jack Ketchum 1946-2018
Olympic Medalists:
6 bronze, 6 silver, 4 gold, 2 silver/bronze, 1 gold/silver
(silver/bronze) Jack Hatfield 1912 swimming - 1500 m freestyle; swimming - 400 m freestyle; swimming - 4x200 m freestyle relay
(silver) Jack Oosterlaak 1920 4x400 m relay
(silver/bronze) Jack London 1928 100 m; 4x100 m relay
(bronze) Gardner Boultbee (a.k.a. Jack) 1932 sailing
(gold) Jack Lovelock 1936 1500 m
(bronze) Jack Metcalfe 1936 triple jump
(gold) Jack Ragland 1936 basketball
(gold/silver) Jack Medica 1936 swimming - 1500 m freestyle; swimming - 400 m freestyle; swimming - 4x200 m freestyle relay
(bronze) Jack Parker 1936 decathlon
(silver) Jack Archer 1948 4x100 m relay
(silver) Jack Gregory 1948 4x100 m relay
(gold) John Winter (a.k.a. Jack) 1948 high jump
(bronze) Jack Taylor 1952 swimming - 100 m backstroke
(silver) Jack Davis 1952; 1956 110 m hurdles
(gold) Jack Yerman 1960 4x400 m relay
(bronze) Jack Horsley 1968 swimming - 200 m backstroke
(silver) Jack Babashoff Jr. 1976 swimming - 100 m freestyle
(bronze) Jack Pierce 1992 110 m hurdles
(silver) Jack Bobridge 2012 cycling - track
Oscar Award Winners:
4 actors
(actor) Jack Albertson 1969 The Subject Was Roses
(actor) Jack Lemmon 1956; 1974 Mister Roberts; Save the Tiger
(actor) Jack Palance 1992 City Slickers
(actor) Jack Nicholson 1976; 1984; 1998 One Flew Over the Cuckoo's Nest; Terms of Endearment; As Good As It Gets
Other Leaders:
1 prime minister
Prime Minister Jack McConnell 2001-2007 Scotland
Rock and Roll Hall-of-Famers:
4 musicians
Jackie Wilson 1987
Jack Bruce 1993 Cream
Jack Casady 1996 Jefferson Airplane
Jack Irons 2012 Red Hot Chili Peppers
Shakespearian Characters:
1 character
Jack Cade Henry VI (2)