It originates in the substitution of one Nordic capital (Stockholm, Sweden) for another (Helsinki, Finland). It entered popular culture when used in the Bruce Willis film Die Hard, by a doctor appearing on a television show and describing the phenomenon. The bumbling host says this refers to "Helsinki, Sweden", and the doctor corrects him, saying "Finland". History
Stockholm bank robbery
In 1973, Jan-Erik Olsson, a convict on parole, took four employees (three women and one man) of Kreditbanken, one of the largest banks in Stockholm, Sweden, hostage during a failed bank robbery. He negotiated the release from prison of his friend Clark Olofsson to assist him. They held the hostages captive for six days (23–28 August) in one of the banks vaults. When the hostages were released, none of them would testify against either captor in court; instead, they began raising money for their defense.Nils Bejerot, a Swedish criminologist and psychiatrist coined the term after the Stockholm police asked him for assistance with analyzing the victims reactions to the 1973 bank robbery and their status as hostages. As the idea of brainwashing was not a new concept, Bejerot, speaking on "a news cast after the captives release" described the hostages reactions as a result of being brainwashed by their captors. He called it Norrmalmstorgssyndromet (after Norrmalmstorg Square where the attempted robbery took place), meaning "the Norrmalmstorg syndrome"; it later became known outside Sweden as Stockholm syndrome.
And here was my first television and my first cartoon and my first superhero — a hero who like my father, was in America—and somehow it all came together for me in a lightning bolt of longing and imagination. My fathers’ absence made perfect sense. He couldnt come back right away because he was busy fighting crime in NYC...as Spider–Man. The diasporic imagination really is its own superpower...I believed I had seen my father on that TV, and if I paid close enough attention it would show him to me again...For the record: my father did eventually return and take us to the States...My father was the worst shock of all. He had no problem laying hands on us kids for the slightest infraction. Beatings like he was making up for lost time. Like he was mad that he had a family...Are you surprised, then, that I was drawn back to the television? Because I was lost, because I wanted help with my English, because my father was a nightmare. And because I was convinced, foolish little fantasist that I was, that somehow my family and I had ended up in the wrong America and that the country and the father I’d first glimpsed on TV in Santo Domingo, the country and father I’d been promised, was still out there somewhere. I just had to find them. Never did.