"Union of the Snake" was the lead single from the band's third album Seven and the Ragged Tiger and preceded its release by one month. It became one of Duran Duran's most popular career singles, hitting #1 in Cash Box and peaking at #3 on both the UK Singles Chart and the US Billboard Hot 100 chart at the end of 1983.

After a song-writing session near Cannes in France, much of the band's third album was recorded at George Martin's Air Studios on the Caribbean island of Montserrat with producer Alex Sadkin, then mixed at 301 Studios in Sydney. Mixing for "Union of the Snake" was done right up to the last minute before the tapes had to be turned over to EMI for pressing.

Lyricist Simon Le Bon (notoriously reticent about explaining his oblique lyrics) hinted in the Duran Duran lyric book The Book of Words that the borderline might be one between the conscious and subconscious minds. In later interviews, he proclaimed that it was a reference to Tantric sex.

Drummer Roger Taylor stated that the beat and drum track was based upon David Bowie's "Let's Dance".

The video for "Union of the Snake" was conceived by Russell Mulcahy, who directed many of the heavy rotation videos for songs from Duran Duran's previous album Rio. However, as Mulcahy was busy preparing to direct the concert film Arena and the documentary film Sing Blue Silver during the band's world tour, the video for "Union" was actually directed by Simon Milne (who also filmed videos for Kajagoogoo and Missing Persons). There was a bit of controversy surrounding the video as it was released to MTV a whole week before the single was released on radio. Radio stations were anxious at the time because they were concerned that channels like MTV might supplant them in the promotion of singles.

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