Songfacts®:

• Harry Styles wrote this synth-pop song with Julian Bunetta, John Ryan and Johan Carlsson. Asked on Twitter what his favorite track on 4 is, Harry replied: "Stockholm was a lot of fun to write."
• Julian Bunetta and John Ryan are frequent 1D collaborators. Harry previously worked with Swedish songwriter and producer Johan Carlsson when they penned (with Savan Kotecha) "A Little Bit of Your Heart" for Ariana Grande.
• The guys sing here about being tied down in a relationship, but loving it. The hostage metaphor is reflected in the song's title, which is a term dating back to the 1970s referring to the psychological phenomenon in which hostages express empathy and have positive feelings toward their captors.
• Stockholm syndrome takes its name from a 1973 robbery of the Kreditbanken at Norrmalmstorg in the Swedish capital. During the six day stand-off, the hostages formed a remarkable bond with their captors, even defending them after they were freed from their ordeal. Both Blink-182 and Muse have also released songs named after the term.