William Walton was 37 at the outbreak of World War 2, and found his plans to write chamber music thwarted. In fact the wartime years turned out to be quite fruitful ones for him, and included several notable film scores. Writing in March 1942, Walton was quite clear about his views of film music - "The music is entirely occasional and is of no use other than what it is meant for ... Film music is not good film music if it can be used for any other purpose ... The music should never be heard without the film.

He wrote the music for Leslie Howard's film about R.J.Mitchell, designer of the Spitfire fighter aircraft "The First of the Few" in June 1942. The film was released in August 1942 and was an outstanding success, to which the music made a great contribution. The march during the opening titles and the dazzling fugue accompanying the assembly of the aeroplanes were particularly impressive, and by the end of the year Walton had rescored them as "Prelude and Fugue". This had its first concert performance in Liverpool on 2nd January 1943 with Walton conducting.

Since by the end of the war Walton's superb music for Laurence Olivier's Henry V had also been arranged as a successful concert suite (though not by Walton himself), one assumes that his trenchant views on the re-use of film music had been moderated!