Songfacts®:

• This is one of several tracks that was produced by Stefani's fellow Voice mentor and longtime collaborator Pharrell for her third solo album. Speaking with AMP radio's Carson Daly, the singer explained the story of the song. "He's like, 'I've got to play you this. I have to play you this,'" she said. "And so he plays me this song, and it's like magic. All it was was a beat and he was singing this melody on top and I just knew, that's it. That night, after shooting all day, we went in the studio all night long, stayed up till four in the morning, came back, got on set and then didn't finish."
  
  Stefani added that completing the song was a challenge, given their busy schedules. "I met him in New York at my fashion show after working all week, and again, we went into the studio all night long," she said "didn't finish, but had these incredible songs coming out, so he came off of tour from Europe, met me in Miami, and we finished the song."
• A snippet of the song was premiered by Gwen Stefani on AMP Radio on October 20, 2014. Pharrell then played the track as part of a live performance during the Odd Future Carnival in early November 2014. The singer-producer played the tune from his cell phone and explained that it addresses feminist issues.
• Gwen Stefani interpolates the Rolling Stones famous "hey, get off my cloud" lyric during the pre-hook portion of the song. The No Doubt frontwoman was a surprise guest on the opening night of the Stones' 2013 50 And Counting tour.
• In the video produced by her longtime collaborator Sophie Muller, Stefani cruises over an animated city from atop a cloud and parties with characters in a nightclub.
• Musician-turned-hair-stylist Richard Morrill filed a lawsuit in January 2017 claiming that this song's chorus bears musical and lyrical similarities to his funk metal band L.A.P.D.'s 1996 track "Who's Got My Lightah." (L.A.P.D. later became the rock outfit Korn).
  
  Morrill stated that he played Stefani the song when he was coloring and styling her hair. She liked it and he gave her a CD containing the tune. Many years later, the hair stylist was surprised to hear what he feels is an interpolation of his "Who's got my lightah? Who got the fire?" lyrics on the chorus of "Spark The Fire," as well as a similar rhythm, melody and background music. Morrell's suit sought damages, a share of the profits and acknowledgment that the copyright of the track was infringed.
  
  Judge Dolly M Gee dismissed the case in October 2018 on the basis that the two songs were not sufficiently similar to constitute copyright infringement.