John or Jack Fitzgerald, or variants, may refer to:

Military

*Sir John Forster FitzGerald (1785–1877), Irish soldier, officer in British Army during the Napoleonic wars and Liberal MP *John Fitzgerald (soldier) (1817–?), American soldier *John Fitzgerald (Medal of Honor) (1873–1948), American Medal of Honor recipient

Nobility

*John FitzGerald, 1st Baron Desmond (died 1261) *John FitzGerald, 1st Earl of Kildare (c. 1250–1316), Irish nobleman *John FitzGerald, 4th Earl of Desmond (died 1399) *John FitzGerald, de facto 12th Earl of Desmond (died 1534) *John Fitzedmund Fitzgerald (died 1589), Irish baron *John FitzGerald, 18th Earl of Kildare (1661–1707) *Lord John FitzGerald (1952–2015), Irish nobleman

Politics and law

UK

*John Fitzgerald (governor) (), Irish soldier and governor of Tangier *John FitzGerald, 15th Knight of Kerry (1706–1741), Irish MP for Dingle *John Fitzgerald (1775–1852), British MP for Seaford 1826–32 *John FitzGerald, Baron FitzGerald (1816–1889), Irish judge and politician *Sir John Fitzgerald (brewer) (1857–1930), Lord Mayor of Newcastle upon Tyne, England, 1914–1915 *Jack Fitzgerald (1873–1929), founding member of the Socialist Party of Great Britain *Jack Fitzgerald (politician) (John Fitzgerald, 1914–1994), Irish Labour Party politician

US

*John Fitzgerald (Wisconsin politician) (c. 1827–1863), Wisconsin banker and politician *John Wesley Fitzgerald (1850–1908), American businessman and politician *John C. Fitzgerald (1863–1928), New York politician *John F. Fitzgerald (1863–1950), aka "Honey Fitz", mayor of Boston, grandfather and namesake of president John F. Kennedy *John J. Fitzgerald (1872–1952), U.S. representative from New York *John I. Fitzgerald (1882–1966), American attorney and politician in Massachusetts *John Moonan Fitzgerald (1923–2008), U.S. jurist and politician *John Warner Fitzgerald (1924–2006), Michigan chief justice *John P. Fitzgerald III, acting United States Trustee for Region 4 of the United States Trustee Program and respondent in ''Siegel v. Fitzgerald''

Other figures in politics and law

*John Daniel FitzGerald (1862–1922), Australian politician *John Fitzgerald (Australian politician) (1864–1936), member of the South Australian House of Assembly *Sir John FitzGerald of Dromana, MP for Dungarvan in the Irish Parliament

Science and medicine

*John Patrick Fitzgerald (1815–1897), New Zealand doctor, community leader and hospital superintendent *John G. FitzGerald (1882–1940), Canadian physician *John Fitzgerald (computer scientist) (born 1965), British computer scientist and Chair of Formal Methods Europe

Sports

American football

*John Fitzgerald (center) (born 1948), former Dallas Cowboys center *John Fitzgerald (quarterback) (born 1975), former quarterback with the af2's Austin Wranglers *John Fitzgerald (offensive guard) (), former University of Central Oklahoma lineman

Association football (soccer)

*Jack Fitzgerald (footballer) (1930–2003), Irish footballer *John Fitzgerald (soccer) (born 1968), Canadian soccer player, businessman & corporate lawyer *John Fitzgerald (footballer) (born 1984), Irish footballer

Baseball

*John Fitzgerald (Rochester Broncos pitcher) (1866–1892), pitcher for the 1890 Rochester Broncos *John Fitzgerald (Boston Reds pitcher) (1870–1921), pitcher for the 1891 Boston Reds *John Fitzgerald (1950s pitcher) (born 1933), pitcher for the 1958 San Francisco Giants *John Fitzgerald (catcher) (), Negro league baseball catcher

Other sports

*John J. Fitz Gerald (1893–1963), American turf racing sportswriter *Jack Fitzgerald (cyclist) (born 1899), Australian cyclist *John Fitzgerald (Australian footballer, born 1961), former Geelong player *John Fitzgerald (Australian footballer, born 1901) (1901–1987), Fitzroy player *John Fitzgerald (tennis) (born 1960), Australian tennis player *John Fitzgerald (pentathlete) (born 1948), American modern pentathlete *John Fitzgerald (rugby union) (born 1961), Irish rugby union international player *Jack Fitzgerald (rugby league) (1925–1965), Australian rugby league player

Others

*John Fitzgerald (priest) (), Dean of Cork *John Anster Fitzgerald (died 1906), English fairy painter and portrait artist *John Driscoll Fitz-Gerald (1873–1946), American scholar and philologist *John D. Fitzgerald (1906–1988), American author of children's books *John Fitzgerald (poet) (1927–2007), English Carmelite priest and philosopher and Welsh-language poet *John D. FitzGerald (born 1952), Irish economist and former director of the Economic and Social Research Institute *John S. Fitzgerald, a frontiersman and erstwhile companion to Hugh Glass