Question: When was the writer of "I Wonder as I Wander" born?

Context articles: Castelar Park
Craig McCracken
Margaret Wander Bonanno
Anita M. Cal
Brian Azzarello
Dessa
Phil Jimenez
John Jacob Niles
Maxie Wander
I Wonder as I Wander

Castelar Park (Parque de Castelar) is located in Badajoz, in Extremadura, Spain.
 Situated south of Guadiana River, its features include tall palm trees and a central pond, frequented by ducks and pigeons; peacocks wander around the park.
 There are monuments dedicated to the romanticist writer Carolina Coronado, who lived in Badajoz, and to Luis Chamizo Trigueros, who was born in Guareña.
 Although Castelar remained neglected for many years, it was renovated during the tenure of Mayor Miguel Angel Celdran Matute (1996-present), making it a venue for fairs, exhibitions, entertainment and leisure.
 Parque Infantil (Playground) is located across the street.
Craig Douglas McCracken (born March 31, 1971) is an American animator, director, writer, and producer.
 He is best known for creating the Emmy-winning animated series "The Powerpuff Girls", "Foster's Home for Imaginary Friends" and "Wander Over Yonder" as well as writing and storyboarding for "Dexter's Laboratory" for Cartoon Network.
 He has been married to fellow animator Lauren Faust since 2004.
Margaret Wander Bonanno (born 1950 as Margaret Wander) is an American science fiction writer, ghost writer and small press publisher.
 She was born in New York City.
Anita M. Cal (born October 14, 1966) is an American author, TV Writer, film producer, and international speaker best known for writing on the TBS family comedies, Tyler Perry's House of Payne and Tyler Perry's Meet the Browns.
 Cal first made a name for herself as the Writer/Producer of the comedy feature Kinfolks, developed by Showtime, Inc., starring In The House TV daughter Maia Campbell.
 Cal is also known as, A.M. Cal, the author of the December 2015 historical novel, Eighth Wonder: The Thomas Bethune Story, the true tale of a slave born blind, feeble, and left for dead who began playing Mozart at the age of three.
 The debut novel was awarded a SELF-e Highlighted Book by Library Journal and made available in libraries throughout the 50 states.
Brian Azzarello (born in Cleveland, Ohio, August 11, 1962) is an American comic book writer and screenwriter.
 He came to prominence with the hardboiled crime series "100 Bullets", published by DC Comics' mature-audience imprint Vertigo.
 In 2011, he became the writer of DC's relaunched "Wonder Woman" series.
Margret Wander (born May 23, 1981), better known by her stage name Dessa, is an American rapper, singer, spoken word artist, writer, and record executive.
 She is a member and CEO of the indie hip hop collective Doomtree.
Phil Jimenez (born July 12, 1970) is an American comics artist and writer, known for his work as writer/artist on "Wonder Woman" from 2000 to 2003, as one of the five pencilers of the 2005–2006 miniseries "Infinite Crisis", and his collaborations with writer Grant Morrison on "New X-Men" and "The Invisibles".
John Jacob Niles (April 28, 1892 – March 1, 1980) was an American composer, singer, and collector of traditional ballads.
 Called the "Dean of American Balladeers", Niles was an important influence on the American folk music revival of the 1950s and 1960s, with Joan Baez, Burl Ives, and Peter, Paul and Mary, among others, recording his songs.
Maxie Wander (January 3, 1933 – November 21, 1977) was an Austrian writer in East Germany (GDR), who was born in a proletarian quarter of Vienna.
 She came to fame after "Guten Morgen, Du Schone" (Good Morning My Lovely) was published, and remains an important figure in East German literature after her death from cancer.
"I Wonder as I Wander" is a Christian folk hymn, typically performed as a Christmas carol, written by American folklorist and singer John Jacob Niles.
 The hymn has its origins in a song fragment collected by Niles on July 16, 1933.