If only classical music were as popular as Hollywood blockbusters... Luckily for Richard Strauss, he hit the posthumous fame jackpot! Strauss and his seminal tone poem, Also sprach Zarathustra, were already known and beloved entities within classical music. By the time Stanley Kubrick used the piece's introduction throughout his film 2001: A Space Odyssey, the two pieces are intertwined in the public's mind. It's practically impossible not to visualize a giant black obelisk once you hear that slow emerging chord rise from the depths of the orchestra.
The story of how Kubrick's movie came to be and it's connection to classical music is fascinating. It was among the first "space operas" and is of significant importance in film history. Indeed, Kubrick was thinking epic when he chose the title. He chose to reference Homer's Odyssey, saying,"[i]t occurred to us that for the Greeks the vast stretches of the sea must have had the same sort of mystery and remoteness that space has for our generation."
The film is largely nonverbal. The movie opens and closes with a total of 45 minutes of zero dialogue; the action is largely dependent on the music accompanying each scene. Kubrick had initially commissioned a score from Alex North and had given the composer a selection of preexisting classical pieces to use as inspiration.
He did the same with Frank Cordell when he decided he didn't like North's score. Cordell's score also didn't satisfy Kubrick and in the end he decided he loved the classical pieces so much that he decided to dump the original score. Hence Strauss's tone poem, as well as Blue Danube by Johann Strauss, two pieces by modern composer György Ligeti, and part of Khatchaturian's ballet Gayane. Kubrick forgot one little detail — he failed to receive permission for the use of any of the recordings featured in his film. Yikes! Ligeti was the only living composer at the time and he did enter into litigation against Kubrick, but it was eventually settled.