Sebastian graduated from Haverford College in 1936 and studied abroad in Rome and Florence in preparation for a foreign service career, although he was still interested in the harmonica.
On the ship back to the United States, he met and was encouraged by Broadway composers Rodgers and Hart, and some time thereafter decided to make the harmonica his career.
[3][5][13][14] Sebastian began his harmonica soloist career in the late 1930s playing nightclubs and cabarets, where his repertoire initially included swing music.
Because very little classical music had been written for the harmonica, Sebastian painstakingly transcribed and adapted suitable works that had been composed for other wind instruments or for violin.
His choice of material enhanced his reputation as a nightclub performer, and by the early 1940s he regularly appeared at elite clubs such as Café Society and the rooms at the Pierre, Waldorf and St. Regis hotels in New York City, and the Palmer House in Chicago.
[3][11][15][16] Despite Sebastian's nightclub success, he aspired to perform in a concert setting (which his contemporary Larry Adler had already accomplished), and to have the harmonica accepted as a serious instrument by classical music critics and the concert-going public.
He also frequently appeared on radio, including performances with the NBC Symphony Orchestra[11][13] and a fourteen-week series of solo programs over the Blue Network,[14] and later on television.
[22][23] In December 1954, he gave a full-length classical music recital at The Town Hall in New York City, then considered essential for an American soloist.
The program was billed as his "debut" in a positive New York Times review by critic Ross Parmenter, even though by then he had already performed as a soloist with a number of major orchestras, and in 1946 had given a previous recital at the Town Hall with Virgil Thomson and Leonard Bernstein.
[17] Parmenter noted that Sebastian, rather than trying to hide the fact that the harmonica was a "small-toned" instrument, made its sound "smaller than need be by the way he envelops it in his hands" and that he worked for "subtlety and poetry within a small dynamic range."
[5] He appeared not only in major cities such as Seoul and Tokyo, but also in less traveled areas such as Okayama, Japan, where he was enthusiastically welcomed by children studying harmonica as part of a program to re-establish music education in local schools.
[3] Many of Sebastian's selections came from the seventeenth and eighteenth century baroque music era,[18] although he adapted some works by more modern composers such as Rimsky-Korsakov, Bartók and Gershwin.
Walter F. Anderson, Anthony Burgess,[25] Luciano Chailly, Henry Cowell, Norman Dello Joio, Alan Hovhaness, George Kleinsinger, Frank Lewin, Donald Martino, Edward Robinson, Alexander Tcherepnin, and Heitor Villa-Lobos all composed works for him.
Starting in the 1940s, Sebastian released a series of records on different labels including Schirmer, RCA Victor, Cadence, Columbia, Decca, Deutsche Grammophon and Heliodor.
[35] The book assumes no prior knowledge of music and teaches the notes, scales and techniques involved in playing the chromatic harmonica, using popular folk tunes as demonstration pieces.
[36] In 1966, following a lengthy concert tour of Africa, Sebastian suffered a heart attack in Rome and after recuperating, remained there, staying until 1976 when he moved to France.
[3][5] (One such work, the "Harmonica Concerto" composed for Sebastian by Henry Cowell in 1962, was finally premiered in 1986 by Robert Bonfiglio with the Brooklyn Philharmonic Symphony Orchestra.[37][38]).
[2] The family lived in Greenwich Village, where according to their son John B. they had a "slightly less than conventional" lifestyle and entertained a variety of artists and musicians, including Garth Williams,[39] Burl Ives, Josh White and Woody Guthrie.