- Dec 1 John Bunch, American jazz pianist (New York Swing Trio), born in Tipton, Indiana (d. 2010)
- Dec 3 Phyllis Curtin, American soprano (NYC Opera, 1953-64), born in Clarksburg, West Virginia (d. 2016)
- Dec 4 (Edna Mae) "Deanna" Durbin, Canadian actress and vocalist (Every Sunday; Three Smart Girls; 100 Men & a Girl), born in Winnipeg, Manitoba (d. 2013)
- Dec 6 Piero Piccioni, Italian jazz pianist, lawyer, film score composer (Swept Away), and conductor, born in Turin, Piedmont, Italy (d. 2004)
- Dec 7 Arne Dørumsgaard, Norwegian composer, born in Fredrikstad, Norway (d. 2006)
- Dec 8 Terence Weil, British cellist (Melos Ensemble), born in London (d. 1995)
- Dec 9 Terence Weil, British cellist (English Chamber Orchestra; Melos Ensemble), born in London (d. 1995)
- Dec 18 Jaime León, Colombian pianist, composer, and conductor Filarmónica de Bogota, 1971-78), born in Cartagena de Indias, Columbia (d. 2015)
- Dec 19 Ludvík Podéšť, Czech composer, born in Dubňany, Czechoslovakia (d. 1968)
- Dec 21 Alicia Alonso, Cuban ballerina and founder of the National Ballet of Cuba, born in Havana, Cuba (d. 2019)
- Dec 21 Joan Dickson, British cellist and teacher, born in Edinburgh, Scotland (d. 1994)
- Dec 22 Harold "Hawkshaw" Hawkins, American country singer (Ozark Jubilee; "Lonesome 7-7203"), born in Huntington, West Virginia (d. 1963)
- Dec 22 Robert Frank Kurka, American composer ("The Good Soldier Schweik"), born in Cicero, Illinois (d. 1957)
- Dec 24 Gerard Thomas Victory, Irish composer, born in Dublin, Ireland (d. 1995)
Steve Allen (1921-2000)
Dec 26 American comedian, composer, writer and TV host (Tonight Show, Steve Allen Show), born in New York City
- Dec 28 Eddy Doorenbos, Dutch jazz and pop vocalist, guitarist (De Millers), and painter, born in The Hague, Netherlands (d. 2013)
- Dec 28 Johnny Otis [Ioannis Veliotes], American R&B musician, songwriter, producer and talent scout ("Willie and the Hand Jive"; "Cupid's Boogie"), known as "the godfather of rhythm and blues", born in Vallejo California (d. 2012)
- Dec 30 Lillian McMurry (née Shedd), American blues producer, audio engineer, and record label owner (Trumpet Records - Sonny Boy Williamson II; Elmore James), born in Purvis, Mississippi (d. 1999) [1]
About December 1921
How Old? 102 years old
Generation: Greatest Generation
Leap Year: No
Chinese Zodiac: Rooster
Star Signs: Sagittarius (Nov 22 - Dec 21), Capricorn (Dec 22 - Jan 19)
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