The Sound of Music premiered on March 2nd, 1965 in New York City, and so March of 2015 marked 50 years since the film's premiere. Even a half-century after its release, this film is still well-known and well-loved, given the many cultural references (and tributes) done over the years. No wonder there were screenings of it all over the world in March and April of 2015!
Why Has "The Sound of Music" Remained So Popular?
I believe the film has kept its popularity largely because of the music; the melodies and lyrics have become iconic because it was so well-composed and meaningful. You just don't hear music like that anymore; for that matter, you just don't see films like "The Sound of Music" much anymore, either. It's a blockbuster without a lot of explosions and CGI effects--it's telling a very big story, and that story is what matters.
I also believe, however, that the film has stayed relevant to humanity because we can't seem to get away from war, no matter how much history we study. The threat of the Third Reich may have passed, but in its place these days is ISIS extremists. (The more things change, the more they stay the same, it seems.) The Sound of Music teaches us that we don't have to watch gritty dark movies to prepare us for gritty dark lives; instead, we can watch uplifting, bright movies to give us courage to face whatever darkness we encounter.
50th Anniversary Interviews, Videos, and Articles
Lady Gaga - Sound of Music 50th Anniversary Tribute at the Oscars, February 2015
"Sound of Music" 50th Anniversary Interviews Playlist