“Layla and Other Assorted Love Songs (1970) is Eric Clapton’s tortured love letter to the wife of his friend, George Harrison … Clapton poured his heart into the songs on Layla,” (American Songwriter). “The five co-writes with (Derek + the Dominos bandmate) Bobby Whitlock – songs like ‘Anyday’ and the bluesy ‘Tell The Truth’ – fuse high-energy rock with some of the most emotional electric blues of all time … Clapton would never again present the blues with such urgency as on the album versions of ‘Nobody Knows You When You’re Down and Out’ and the Big Bill Broonzy staple ‘Key to the Highway.’
‘Bell Bottom Blues,’ the only song on the album Clapton wrote entirely by himself, is a portrait of a man on the brink of collapse. After the record’s release, Clapton sank into depression and addiction. As Whitlock recalls, one of the great all-time rock and roll bands ‘didn’t break up, it just kind of dissipated … Eric locked himself away for a couple of years, and that was that.'”
Starting in a slightly de-tuned C major, the tune shifts up to A major for its plaintive chorus (heard for the time between 0:41 – 1:16). Verse 2 reverts to the original key. The pattern continues from there.