This was written by Morrissey and guitarist Boz Boorer. Boorer has collaborated with Morrissey on a number of other singles including the 1994 UK Top Ten hit "The More You Ignore Me, The Closer I Get."
American Singer - songwriter Kristeen Young supplied the operatic background vocals. Young opened for Morrissey during his 2006-07 "Ringleader of the Tormentors" tour.
"(What's So Funny 'Bout) Peace, Love, and Understanding" was written by Nick Lowe in 1974. The original version with his group Brinsley Schwarz was kind of somber, but Elvis Costello made it a classic with his 1978 uptempo take.
It was never a big hit, but "She's A Rainbow" became one of the most popular Rolling Stones songs in the digital age when it started showing up in commercials (iMac, Photoshop), and TV shows (American Horror Story: Coven, Ted Lasso).