The bank robbery and hostage situation that led to the coining of the term "Stockholm syndrome" began on this day in history, Aug. 23, 1973.
On that date, Jan-Erik Olsson, an escaped prisoner who was sentenced to three years in prison for grand larceny, burst into Sveriges Kreditbanken, located in Stockholm's Norrmalmstorg square, armed with a submachine gun.
In an attempt to hide his identity as a native Swede, Olsson put on an American accent and said, in English, "The party has just begun," according to the website of the History Channel.
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As it turned out, the "party" had indeed just begun: After wounding a police officer, Olsson then held four employees of the bank hostage for five days.
Olsson demanded roughly $700,000 in Swedish and foreign currency, access to a getaway car and the release of Clark Olofsson, a man Olsson had befriended while in prison.
While these demands were met by the Swedish police — including a full tank of gas for the supplied Ford Mustang getaway car — Olsson did not release the four hostages nor did he agree to actually leave the bank, said the History Channel.
The whole affair played out on television.
The hostage situation was the first Swedish crime to be aired in real-time.
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On August 28, the hostage situation finally ended after Swedish police fired tear gas into the bank. Olsson and Olofsson left the vault and were arrested.
No physical harm was done to any of the four hostages, but their behavior throughout their ordeal intrigued mental health professionals.
"The captives quickly forged a strange bond with their abductors," noted the History Channel.
Olsson gave one of the hostages a wool jacket when she was cold, and "gave her a bullet from his gun as a keepsake," the same source noted.
Another hostage, Elisabeth Oldgren, was allowed out of the bank vault, albeit attached to a rope, when she said she was experiencing claustrophobia.
"I remember thinking he was very kind to allow me to leave the vault," Oldgren told The New Yorker a year after she was freed.
The hostages were on a first-name basis with their captors by the second day of their captivity — and were even concerned for their overall welfare.
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Hostage Kristin Enmark told Swedish Prime Minister Olof Palme that she "fully trust(ed) Clark and the robber" and that she was "not desperate."
"They haven’t done a thing to us. On the contrary, they have been very nice. But, you know, Olof, what I am scared of is that the police will attack and cause us to die," she said.
Enmark also insisted that the police allow Olsson and Olofsson to leave the vault before any of the hostages.
"No, Jan and Clark go first — you’ll gun them down if we do," she said.
Both of the robbers were arrested without incident and were sentenced to years in prison.
While in prison, they were visited by their former hostages, said the History Channel. Both have since been released.
Olsson is believed today to be in his early 80s (he was born in 1941).
Olafsson, born in 1947, is thought to be 76 years old.
The seemingly bizarre bond between the hostages and their captors led a criminologist and a psychologist to create the term "Stockholm syndrome," according to the Cleveland Clinic's website.
Those with Stockholm syndrome have "positive feelings toward the captors or abusers, sympathy for their captors’ beliefs and behaviors, (and) negative feelings toward police or other authority figures," said the Cleveland Clinic.
While Stockholm syndrome is not officially recognized by the American Psychiatric Association, "all health care providers recognize behaviors that result from a traumatic situation," said the Cleveland Clinic.
"The criteria for PTSD or acute stress disorder and some treatments are often similar to Stockholm syndrome."
The term "Stockholm syndrome" entered the American consciousness with the 1974 kidnapping of newspaper heiress Patty Hearst.
Hearst, 19, was kidnapped by armed members of the Symbionese Liberation Army (SLA), a leftist group, from her apartment in Berkeley, California, on Feb. 4, 1974.
Less than two months after her kidnapping, the SLA released a tape of Hearst saying she had officially joined the group, taken the name "Tania," and had "joined their fight to free the oppressed," said the FBI.
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She was arrested 19 months after her kidnapping for her role in a bank robbery on behalf of the SLA.
Hearst claimed she was brainwashed and abused by the group.
Despite these claims, she was found guilty, noted the FBI.
President Jimmy Carter pardoned her in 1979, two years into her sentence.
