How did Jack Unterweger die? Details about World's Most Notorious Killers subject explored

Peacock's latest true crime docu-series, World's Most Notorious Killers, explored five of the most prolific murderers, including Jack Unterweger, who was also known in the crime world as the Vienna Strangler. He was convicted of over 10 murders and committed suicide shortly after being sentenced for the crimes.

The twisted murderer is the subject of World's Most Notorious Killers episode 2, which premiered on Peacock on September 17, 2024. The synopsis for the episode reads:

"Police in Vienna, Austria, are perplexed by a series of deaths; when similar murders occur in Los Angeles, detectives realize they are hunting the world's first transatlantic serial killer: a celebrity hiding in plain sight."

Jack Unterweger was convicted and sentenced when he was much younger but he not only got out of prison but he also continued to commit heinous acts of violence, escaping the law for years, before he was finally caught and sentenced again. This time, however, Jack fashioned a rope from shoelaces and a string from his trousers and strangled himself to death, much like how he killed his victims.

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Who was Jack Unterweger and what did he do?

Jack Unterweger was a prolific Austrian serial killer, who was convicted of over ten murders and is rumored to have committed many more. Jack Unterweger was born to Theresia Unterweger and Jack Becker on August 16, 1950. His father remained largely absent from his life and his mother was a bartender, who also allegedly did s*x work.

He had a very turbulent upbringing, which also saw him move in with his grandfather in Carinthia, Austria, following his mother's alleged arrest. He started committing crimes early in his life and by 1974, Jack was arrested 16 times, with crimes ranging from petty theft to brutal assaults.

Then in 1974, Jack brutally murdered 18-year-old Margaret Schäfer. He was arrested and sentenced to life in prison.

However, this was hardly the end of his criminal career.

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Jack Unterweger killed more people in his second stint

In prison, Jack started writing and embracing his creative side. Soon, he started garnering public sympathy after writing his autobiography, Purgatory or The Trip to Prison – Report of a Guilty Man. Soon, pressure started building on the authorities to release him as everyone thought he deserved a second chance.

He was ultimately released in May 1990 and was hired by Österreichischer Rundfunk, Austria’s national broadcaster, to cover crime stories. While Unterweger continued covering crimes and relishing in his fame, three murders took place in Vienna, where all the victims were s*x workers.

Soon, four more victims were found in Graz. Jack Unterweger continued covering these crimes and was even sent to the United States for a project. When he went there, three s*x workers were murdered in a similar fashion.

It did not take long for the authorities to connect the dots, which implied that Jack was present in the exact cities where the crimes took place. Moreover, he was also spotted by people in the areas the crimes took place in, who later identified him.

As police began tracking him, Unterweger fled with his girlfriend. After a brief period of escaping the law, he was finally arrested on February 27, 1992, in Florida.

After being extradited to Austria, he was charged with 11 counts of murder. He was found guilty of nine of them. However, on the day of his conviction, Jack Unterweger killed himself in Graz-Karlau Prison using a rope from shoelaces and a string from his trousers. He killed himself in the same manner he killed his victims.

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World's Most Notorious Killers episode 2 covers this in more detail.