- Sep 1 Matt Higgins Doran, American composer (Roland the Minstrel Pig; Faculty Meeting), pedagogue (St. Mary's College), and magician, born in Covington, Kentucky (d. 2016)
- Sep 1 Willem Frederik Hermans, Dutch writer (Mandarins on Sulfuric Acid; The Darkroom of Damocles), born in Amsterdam, Netherlands (d. 1995)
- Sep 3 Harry Landers [Sorokin], American actor (Star Trek, Ben Casey, Drive a Crooked Road), born in New York City (d. 2017)
- Sep 3 John Aston Sr., English soccer striker (17 caps; Manchester United 253 games), born in Prestwich, England (d. 2003)
- Sep 3 Marguerite Higgins, American reporter and war correspondent, Pulitzer prize winner (d. 1966)
- Sep 3 Thurston Dart, English harpsichordist and conductor, born in Surbiton, London (d. 1971)
- Sep 5 Jack Valenti, American political advisor and film executive, born in Houston, Texas (d. 2007)
- Sep 6 Carmen Laforet, Spanish author, born in Barcelona, Spain (d. 2004)
- Sep 6 Norman Joseph Woodland, American co-inventor of the barcode, born in Atlantic City, New Jersey (d. 2012) [1]
- Sep 7 Arthur Ferrante, American pianist and composer (Ferrante & Teicher - Exodus), born in New York City (d. 2009)
- Sep 7 Josep Lluís Núñez, Spanish President of FC Barcelona (1978 - 2000), born in Guriezo, Cantabria, Spain (d. 2018)
- Sep 8 Hans Ulrich Engelmann, German composer (Ophelia), born in Darmstadt, Germany (d. 2011)
- Sep 8 Harry Secombe, Welsh actor, comedian, singer and goon (The Goon Show; Oliver!), born in Swansea, Wales (d. 2001)
- Sep 8 Norris Turney, American jazz flute and saxophone player (Billy Eckstine, 1947-48; Duke Ellington Orchestra, 1968-73), born in Wilmington, Ohio (d. 2001)
- Sep 9 Andrzej Dobrowolski, Polish classical and experimental composer, born in Lwów, Poland (now Ukraine) (d. 1990)
- Sep 11 Edwin Richfield, British actor (Interpol Calling, The Avengers), born in London England (d. 1990)
- Sep 12 Frank McGee, American news anchor (NBC Evening News), born in Monroe, Louisiana (d. 1974)
- Sep 12 Stanislaw Lem, Polish sci-fi author (Solaris, Invincible), born in Lwów, Second Polish Republic (d. 2006)
- Sep 14 Hughes Rudd, American news anchor (CBS Morning News), born in Waco, Texas (d. 1992)
- Sep 15 Jan Frank Fischer, Czech composer, born in Louny, Czech Republic (d. 2006)
- Sep 15 Norma MacMillan, Canadian voice actress (Casper the Ghost), born in Vancouver (d. 2001)
- Sep 16 Fritz Geissler, German composer, born in Wurzen, Saxony (d. 1984)
- Sep 16 John Hendricks, American lyricist and singer (Lambert, Hendricks & Ross), born in Newark, Ohio (d. 2017)
- Sep 16 Ursula Franklin, German-born Canadian physicist, educator and activist (developed archaeometry), born in Munich, Germany (d. 2016) [1]
- Sep 16 William Johnston, Chaplain to Queen of Scotland, born in Edinburgh (d. 2005)
- Sep 17 Virgilio Barco Vargas, Colombian politician and engineer, President of Colombia (1986-90), born in Cúcuta, Colombia (d. 1997)
- Sep 18 Gerald Hartley, American composer, choral director, and educator, born in Spokane, Washington (d. 2021)
- Sep 19 Billy Ward, American singer and songwriter (Billy Ward and his Dominoes), born in Savannah, Georgia (d. 2002)
- Sep 19 Joan Tozzer, American figure skater, born in Dedham, Massachusetts (d. 2012)
- Sep 19 Paulo Freire, Brazilian educator and philosopher (critical pedagogy), born in Recife, Pernambuco, Brazil (d. 1997)
- Sep 20 (Foreststorn) "Chico" Hamilton, American jazz drummer (Lester Young; Gerry Mulligan; Count Basie), and bandleader (Chico Hamilton Quintet), born in Los Angeles, California (d. 2013)
- Sep 20 Melvin "Slappy" White, American comedian and actor, born in Baltimore, Maryland (d. 1995)
- Sep 24 Jim McKay, American sportscaster (ABC's Wide World of Sports; American Sportscasters Association HOF), born in Philadelphia, Pennsylvania (d. 2008)
- Sep 24 Leonard Salzedo, British orchestral, ballet, and film composer (The Witch Boy; Requiem Sine Voxibus, Hammer Films), born in London, England (d. 2000)
- Sep 25 Remy C. van de Kerckhove, Flemish poet, born in Mechelen, Antwerp, Belgium (d. 1958)
Robert Muldoon (1921-1992)
Sep 25 New Zealand politician (Prime Minister, 1975-1984), born in Auckland
- Sep 27 Dennis Nineham, British theologian (Synod and Doctrine Commission), born in Southampton, England (d. 2016)
- Sep 29 Miklós Jancsó, Hungarian director (Muzsika, Aube, Pacifist), born in Vac, Hungry (d. 2014)
- Sep 30 Deborah Kerr, American actress (The King & I, Night of Iguana), born in Helensburg Scotland (d. 2007)
- Sep 30 Eileen Chang, Chinese-American writer, scriptwriter and feminist, born in Shanghai, China (d. 1995)
- Sep 30 Pedro Knight, Cuban-American trumpeter, husband and manager of legendary singer Celia Cruz, born in Havana, Cuba (d. 2007)
About September 1921
How Old? 102 years old
Generation: Greatest Generation
Leap Year: No
Year of the Rabbit
Year of the Dragon
Year of the Snake
Year of the Horse
Year of the Goat/Sheep
Year of the Monkey