The 1974 “Swallows and Amazons” film music was composed by Wilfred Josephs, best known for producing the theme music for “I,Claudius”, “Enemy at the Door”, “The Prisoner” and “Pollyanna”. 

You can listen to his introduction & end title music for “Swallows and Amazons” below, while the film itself is available on BBC iPlayer for UK viewers until 31st January. Sophie Neville, who played Titty Walker in the film, has written an article about meeting Wilfred Josephs during filming, as well as a book about making the film.

https://www.youtube.com/watch?v=xXFSTzq36tQ?rel=0