Born to a Viennese prostitute and an unknown American soldier. He grew up in poverty with his abusive, alcoholic grandfather in a one-room cabin.
He was in and out of prison several times during his youth for assaulting local prostitutes. He murdered 18-year-old German Margaret Schäfer in 1974 by strangling her with her own bra.
He was sentenced to life in prison and used that time to study. He became an author of short stories, poems, plays, and an autobiography, "Fegefeuer – eine Reise ins Zuchthaus" which was a success with critics and the public. He was released after only 16 years of his life term, thought to be a successful "resocialized" prisoner. Law enforcement later found, however, that he had killed six prostitutes in Austria in the first year after his release.
In 1991, he was hired by an Austrian magazine to write about crime in Los Angeles, California, writing articles about prostitution and riding around town with the local police. During his time in Los Angeles, the three prostitutes Shannon Exley, Irene Rodriguez, and Sherri Ann Long were beaten, sexually assaulted with tree branches, and finally strangled with their own brassieres.
Back in Austria, law enforcement had enough evidence for his arrest, but he was gone by the time they entered his home. After law enforcement chased him through Europe, Canada and the United States of America, he was finally arrested by the FBI in Miami, Florida on February 27 1992. While a fugitive, he had time to call Austrian media to try to convince them of his innocence.
Return to Austria
Back in Austria, he was charged with eleven homicides. The jury found him guilty of nine murders because no cause of death could be determined for two of them, as nothing was found of them but bones. On June 29 1994 he was sentenced to life in prison without possibility of parole. That night, he took his own life by hanging himself with his pants using an identical knot to those used on the murdered prostitutes. Because he died before he could appeal the verdict, it was never legally valid. Thus, according to Austrian law, Unterweger is to be regarded as innocent. Due to this legal error, Unterweger's case was carefully considered during creation of newer laws, which were to be enforced by the European Union.
The social history of Jack Unterweger is still researched by American academia and law enforcement, because of Johann's personal fixation with a historical figure that is still only known as "Jack the Ripper" (who remains an unknown serial killer from the 19th century). With FBI evidence against Johann Unterweger very closely reflecting the known evidence of Jack the Ripper, along with the thrifty Austrian-to-American first name translation for investigators, Johann earned the nickname of "Jack".
- Austrian musician Falco composed the song "Jeanny", which represented the life of Jack Unterweger. The song caused a scandal.