Upon leaving school, he briefly obtained employment as an apprentice locksmith in Neuf-Brisach (now part of France) before opting at age 15 to enrol in a military academy in the town of Breisach.

However, after five months of military service, he began to suffer periodic lapses of consciousness which, although initially described by a medical professional as being sudden signs of anxiety neurosis, were subsequently diagnosed as being "equivalent to epilepsy" in October 1895.

[7] Although briefly transferred to a Hanover hospital for psychiatric evaluation, he would be certified as being "incurably deranged"[8] and unfit to stand trial by a psychologist named Gurt Schmalfuß.

[12] Discharged from the military under medical terms[13] described as being "probable" dementia praecox,[12] Haarmann was awarded a monthly pension of twenty-one gold marks.

On one occasion when working legitimately as an invoice clerk, Haarmann became acquainted with a female employee with whom he later claimed to have robbed several tombstones and graves between 1905 and 1913 (he was never charged with these offences).

Upon his release from prison in April 1918, he initially moved to Berlin before opting to return to Hanover, where he briefly lived with one of his sisters before renting a single-room apartment in late August 1918.

Despite the manipulation Haarmann endured at the hands of his accomplice, he later claimed to tolerate the capitulation as he craved Grans' companionship and affection,[46] adding: "I had to have someone I meant everything to.

No human remains identified as belonging to Schulze were ever found, although most of his clothing was in the possession of Haarmann's landlady, Elisabeth Engel, at the time of his arrest.

Subsequent enquiries by Erdner's parents revealed the youth became acquainted with a Detective Fritz Honnerbrock (a pseudonym used by Haarmann) shortly before his disappearance.

Haarmann would confess it had taken him four separate trips to carry de Vries's dismembered remains—carried in the leather bag which had belonged to Friedrich Koch—to the location where he had disposed of them.

Determined to be that of a young male aged between 18 and 20 and bearing evidence of knife wounds, police were sceptical as to whether a murder had been committed or whether the skull had either been discarded in this location by grave robbers, or placed there in a tasteless prank by medical students.

In addition, various newspapers responded to these discoveries and the resulting rumours by harking to the disproportionate number of young people who had been reported missing in Hanover between 1918 and 1924.

[63] Suspicion for the discoveries quickly fell upon Haarmann, who was known to both the police and the criminal investigation department as a homosexual who had amassed fifteen previous convictions dating from 1896 for various offences including child molestation and the sexual assault and battery of a minor.

He was soon observed arguing with a 15-year-old boy named Karl Fromm, then approaching police and insisting they arrest the youth on the charge of travelling upon forged documents.

Two former tenants informed police that, in the spring of 1924, they had discreetly followed Haarmann from his apartment and observed him discarding a heavy sack into the Leine River.

[71] The turning point came on 29 June when clothes, boots, and keys found stowed at Haarmann's apartment were identified as belonging to a missing 18-year-old named Robert Witzel.

When Witzel's jacket was found in the possession of his landlady and he was confronted with various witnesses' testimony as to his destroying identification marks on the clothing, he broke down and had to be supported by his sister.

[n 7] Faced with this latest evidence, and upon the urging of his sister,[75] Haarmann confessed to raping, killing, and dismembering many young men in what he initially described as a "rabid sexual passion"[75] between 1918 and 1924.

[76] Nonetheless, Haarmann was insistent that his passion at the moment of murder was invariably "stronger than the horror of the cutting and the chopping" which would inevitably follow, and would typically take up to two days to complete.

[46][85] The trial was one of the first major modern media events in Germany, and received extensive international press coverage, being described as the "most revolting [case] in German criminal history.

"[90][n 9] Numerous exhibits were introduced into evidence in the opening days of the trial, including 285 sections of the skeletal structure—particularly skulls and thigh bones[91]—recovered from the Leine River and forensically determined as belonging to young men under 20 years of age,[92] the bucket which he used to store and transport human remains, and the extensively bloodstained camp bed upon which he had killed many of the victims at his Rote Reihe address.

[95] The police apparently never suspected him for any of the cases of missing boys and young men in Hanover in 1923 and 1924, even though some of the victims were last seen in his company, and he had a long criminal record that included charges of sexual assault and battery.

Upon hearing the sentence, Haarmann stood before the court and proclaimed, "I accept the verdict fully and freely",[97] before adding: "I [shall] go to the decapitating block joyfully and happily.

Upon receipt of the news, he observed prayer with his pastor, before being granted his final wishes of an expensive cigar to smoke and Brazilian coffee to drink in his cell.

[123] In the case of Hermann Wolf, police established that prior to the youth's disappearance, he had informed his father he had conversed with a detective at Hanover station.

[125] In September 1918,[40] Haarmann is believed to have killed a 14-year-old named Hermann Koch, a youth who disappeared just weeks prior to his first confirmed victim, Friedel Rothe.

[111] Haarmann is also strongly suspected of the murder of Hans Keimes, a 17-year-old Hanover youth who was reported missing on 17 March 1922[111] and whose nude, bound body was found in a canal on 6 May.

[42] Two weeks before the disappearance of Keimes, Haarmann had returned to his Neue Straße apartment, having served six months in a labour camp for several acts of theft he committed in August 1921.

[132] The murders committed by Haarmann stirred much discussion in Germany regarding methods used in police investigation, the treatment of mentally ill offenders, and the validity of the death penalty.

The discovery of the murders subsequently stirred a wave of homophobia throughout Germany, with one historian noting: "It split the [gay rights] movement irreparably, fed every prejudice against homosexuality, and provided new fodder for conservative adversaries of legal sex reform.