Songfacts®:

• This is an adaptation of a classical piece written in 1942 by the American composer Aaron Copland. It was ELP keyboard player Keith Emerson who initiated the idea, transposing the song so the keyboard was the main instrument. According to Greg Lake, the recording came together spontaneously in the studio - as Emerson was playing the piece, Lake came in with a shuffle pattern on bass, and Carl Palmer added his drums. The engineer was rolling tape, and this first time the band played the song through is what made the album.
• Emerson, Lake & Palmer was one of the most popular bands of the '70s, but surprisingly, this was their only song to enter the UK singles chart. They released very few singles in the UK, and never issued many of their most popular songs there, including "Lucky Man" and "Karn Evil 9."
  
  Greg Lake matched this song's #2 UK chart position two years earlier with this solo release, "I Believe In Father Christmas."
• The album version of this song runs 9:46, but was edited down to 2:57 for single release.
• Aaron Copland's original classical piece was written in response to America's entry into the Second World War. It was inspired by a speech given by the US vice president, Henry A. Wallace, referring to the "century of the common man."