When William Steinberg was appointed music director of the Boston Symphony in 1969 as successor to Erich Leinsdorf, he attained the pinnacle of his career. No previous conductor had headed two top-ten US orchestras simultaneously. It was a condition of his Boston position that he could continue to work in Pittsburgh with the orchestra that he had headed since 1952.

Born as Hans Wilhelm Steinberg in Cologne on 1 August 1899, he studied at the local conservatory with the conductor Hermann Abendroth and the pianist Lazzaro Uzielli, a Clara Schumann pupil. On graduating in 1920 he became Otto Klemperer's assistant at the Cologne opera house. In 1929 he was appointed music director in Frankfurt. Relieved of his post by the Nazis in 1933, he conducted concerts in Frankfurt and Berlin under the auspices of the Jewish Cultural League before emigrating to Palestine in 1936 to take over the Palestine Orchestra (now Israel Philharmonic Orchestra). At Toscanini's invitation he went to the United States in 1938 to assist in forming and training the new NBC Symphony Orchestra. In 1945 he assumed the music directorship of the Buffalo Philharmonic, where he liked to refer to himself as "Buffalo Bill".

The Steinberg/Boston collaboration with RCA was unfortunately ill-fated and short-lived. Not because of the repertoire, but plummeting sales and spiraling costs plaguing the American recording industry in general persuaded RCA to let it's contract with the Boston Symphony lapse after 52 years' association. Gramophone magazine's Peter Quantrill claimed in 2018 that Steinberg was "the most under-recorded of great conductors in the second half of the last century."

In 2004 the critic Richard Freed wrote of the Schubert Ninth (CD 1) and Bruckner Sixth (CD 2) Symphonies: "Both [are] vital and inspiring performances, free of the monumentalizing all too often inflicted on such music: they are among the best entries in his discography and among the finest recordings of the works." According to John L. Holmes in Conductors on Record, they were also Steinberg's favorites among his own recordings. Mendelssohn's own orchestration of the Scherzo from his Octet and Stravinsky's Scherzo fantastique and Scherzo a la russe, coupled on CD 3 with formidable virtuoso renderings of orchestral showpieces by Dukas, Richard Strauss and Saint-Saens, were originally prepared for release on LP LSC-3155 but remained unpublished - until now.

This survey of RCA Boston Symphony recordings during the Steinberg era is rounded off with 1970 tapings of Dvorak's "New World" Symphony and Carnival Overture (CD 4) from the same recording period by Arthur Fiedler, former BSO violinist and longstanding conductor of the Boston Pops. His recordings of mainly light repertoire for RCA generated total sales of well over 50 million. Nevertheless, it was his ambition to record a major symphony, and here RCA belatedly granted his wish, placing the full Boston Symphony Orchestra at his disposal for the first and only time.

All recordings in the set have been newly transferred and remastered from the 3-track (CD 1), 4-track (CDs 2, 3 [1-6], 4) and 2-track (CD 3 [7-9]) analog tapes using 24 bit / 192 kHz technology.