This is one of several heartbreaking ballads on Duffy's second album, Endlessly. The singer told US Magazine how the record's melancholy subject matter was inspired by times when she has been upset in her own life. Said Duffy: "I get let down, but I've never been heartbroken - I've been hurt, but not broken. I go through all these different emotions and I reflect. When I'm a part of something that doesn't make me feel good, it compels me to put pen to paper and write songs."
"It's the End of the World As We Know It (And I Feel Fine)" was inspired by a dream where Michael Stipe conjured up images of people with the initials L.B.: Lester Bangs, Leonid Breshnev, Lenny Bruce and Leonard Bernstein.