He worked as a police informant for years. That's likely part of why nobody suspected him for so long.
Fritz Haarmann was a German serial killer who murdered at least 24 young men and boys in Hanover, Germany, between 1918 and 1924, earning the nickname "the Vampire of Hanover" for his method of killing.
A Troubled Early Life
Haarmann was born in Hanover in 1879, the youngest of six children. As a young man he developed epilepsy, was discharged from military school because of it, and built up a long record of petty crime — theft, fraud, sexual offenses against boys — well before his killing began. He spent time in psychiatric institutions and was declared, in the language of the era, "morally inferior." None of that stopped him from later becoming a paid police informant, a role that gave him a working relationship with the very officers who might otherwise have investigated him.
How He Operated
Haarmann sold secondhand clothes and meat in Hanover, a city then flooded with displaced and homeless young men in the aftermath of World War I. He would approach vulnerable teenagers and young men, often at the train station, offering them lodging or work, then kill them, typically by biting through the throat during a sexual encounter — the detail behind his nickname. He dismembered his victims afterward and disposed of the remains in the nearby Leine River, keeping and selling their belongings.
Getting Away With It for Years
Nearly 600 young men and boys were reported missing in Hanover in 1923 alone. Haarmann's arrest only came in 1924, after children discovered human skulls and bones along the riverbank, prompting a formal dredging operation. Investigators searching his apartment found hundreds of items of clothing, though only about a quarter could later be tied definitively to known victims.
Rumors That Were Never Proven
Public rumor at the time held that Haarmann sold his victims' flesh disguised as pork on Hanover's black market — a claim that has followed the case ever since and shows up in nearly every retelling. Haarmann himself denied it firmly, and no evidence has ever confirmed it actually happened. It remains, a century later, an unverified rumor rather than an established fact.
Trial and Execution
Haarmann's December 1924 trial became one of the first major media sensations in German criminal history, drawing intense international press coverage. He cooperated extensively with investigators throughout, helping locate additional remains, though he grew visibly distressed whenever questioned about decapitation specifically. He was tried for 27 murders and convicted of 24. He was sentenced to death and executed by guillotine in April 1925, reportedly telling officials beforehand that he repented but didn't fear death.
A Lasting, Complicated Legacy
Because Haarmann was gay and many of his victims were young men he'd approached in that context, his case was seized on at the time to fuel broader persecution of gay men in Germany — a use of the case that reflected the prejudices of the era rather than anything meaningful about the crimes themselves. The remains of his identified victims were eventually buried together in Hanover's Stöckener Cemetery, where a memorial stone was placed in 1928.
Frequently Asked Questions
Did Fritz Haarmann really sell human flesh as meat?
This has never been confirmed. It was a rumor circulating in Hanover at the time, which Haarmann denied, and no evidence has ever proven it true.
How many people did he kill?
He was tried for 27 murders and convicted of 24.
How was he eventually caught?
Children found human bones along the Leine River in 1924, prompting a search that led investigators to his apartment and, ultimately, his confession.