From the cinematic viewpoint, the careers of Max Steiner, Franz Waxman and Erich Wolfgang Korngold seem to have parallels in that they all moved to Hollywood from a traditional classical musical education in Europe. Out of this group, though, Korngold was by far the most promising classical composer. His father Julius was a music critic in Vienna and the young Erich Wolfgang was a precocious child prodigy impressing composers of the stature of Gustav Mahler, Richard Strauss and Giacomo Puccini with his composition skills at age 9. He then studied under Zemlinsky among others. By the early 30s, Korngold was firmly on the map as a classical composer of note with a number of operas in the grand Wagnerian style established in the repertoire, and Korngold himself was professor at the Vienna State Academy of Music. However at this time anti-Semitism was on the increase in Europe, and therefore Korngold readily accepted an invitation from director Max Reinhardt to move to Hollywood initially to adapt Mendelssohn's "A Midsummer Night's Dream".
His subsequent film scores were a major success in Hollywood with his wonderful command of the orchestra and sweeping romantic sounds which have influenced many later composers such as John Williams. He did much of his work for the swashbuckler movies (most often featuring Errol Flynn as the hero) which were popular in his day, including "Captain Blood", "The Adventures of Robin Hood", "The Sea Hawk" and "The Private Lives of Elizabeth and Essex", and also "Kings Row" with Ronald Reagan. Two of his scores were rewarded with Oscars, namely "The Adventures of Robin Hood" and "Anthony Adverse". After World War II, Korngold returned to Vienna and was to incorporate some music from his films (e.g. "Anthony Adverse") into other works, but never quite managed to recreate his earlier classical successes. Whether this was because his romantic style was now out of vogue or because the "film composer" label had now tarnished his image of respectability is not clear.
A perfect example of Korngold's post-Hollywood concert works and their relationship to his film music is his Violin Concerto. This was the first piece written after WWII, the composer having dedicated himself to support his family through writing only film music until Hitler had been defeated. Korngold borrows themes from his movie scores in all three movements of the Concerto. The soaring violin solo which opens the concerto was taken from the Errol Flynn feature "Another Dawn" (1937), while the entrancing second theme originally accompanied a love scene in William Dieterles 1939 movie "Juarez". The lyrical principal theme of the central Romance, first heard on solo clarinet and quickly adopted by the violin, was originally used in the Oscar-winning score for "Anthony Adverse" (1936). The virtuosic Rondo finale contrasts a playful dance-like theme with a down-to-earth, folk-like second theme borrowed from Korngold's 1937 score for Mark Twain's "The Prince and the Pauper", ending with a fast and furious coda.
An interesting fact to note as well as writing film music himself, Korngold's classical music has also been used in films. "The Big Lebowski" features music from his opera "Die Tote Stadt".
Some of Korngold's music can be found on compilation CDs, but increasingly there are releases of original soundtracks or restored scores. If you are new to the film music of Korngold, these albums are a good place to start exploring.