Peter Kürten was born into a poverty-stricken, abusive family in Mülheim am Rhein on 26 May 1883, the third of thirteen children (two of whom died at an early age). Kürten's parents were both alcoholics who lived in a one-bedroom apartment, and although Kürten's father was an efficient workman who earned sufficient money to provide food, shelter and clothing for his family, the relationship between his parents was marred by the domestic violence Kürten's father would inflict upon both his wife and children, particularly when he was drunk. When intoxicated, Kürten's father would often force his wife and children to assemble in one room before ordering his wife to strip naked and engage in intercourse with him as his children watched. He would be jailed for 15 months in 1894 for committing Incest with his eldest daughter, who was aged 13. Shortly thereafter, Kürten's mother obtained a separation order, and later remarried and relocated to Düsseldorf.

In 1888, Kürten attempted to drown one of his playmates. Four years later, he befriended a local dog-catcher who lived in the same building as his family, and began accompanying him on his rounds. This individual would often torture and kill the animals he caught, and Kürten soon became an active and willing participant in torturing the animals himself.

In 1897, Kürten left school. At his father's insistence, he obtained employment as an apprentice molder. This apprenticeship would last for two years before Kürten stole all the money he could find in his household, plus approximately 300 marks from his employer, and ran away from home. He relocated to Koblenz, where he began a brief relationship with a prostitute two years his senior whom he claimed willingly submitted to every form of sexual perversion he demanded of her. He was apprehended just four weeks later and charged with both breaking and entering and theft, and subsequently sentenced to one month's imprisonment. He was released from prison in August 1899 and reverted to the life of petty crime he had lived before his arrest.

Kürten claimed to have committed his first murder in November 1899. In his 1930 confessions to investigators, Kürten claimed to have "picked up an 18-year-old girl at the Alleestraße" and persuaded her to accompany him to the Hofgarten, where he claimed to have engaged in sex with the girl before strangling her to death with his bare hands.

Shortly thereafter, in 1900, Kürten was arrested for fraud. He would be rearrested later the same year on the same charge, although on this second occasion, charges pertaining to his 1899 Düsseldorf thefts, plus the attempted murder of a girl with a firearm were added to the indictment. Consequently, Kürten was sentenced to four years' imprisonment in October 1900. He served this sentence in the suburb of Derendorf.

Released in the summer of 1904, Kürten was drafted into the German Army; he was deployed to the Alsatian city of Metz to serve in the 98th Infantry Regiment, although he soon deserted. That autumn, Kürten began committing acts of arson, which he would discreetly watch from a distance as emergency services attempted to extinguish the fires. The majority of these fires were in barns and haylofts, and Kürten would estimate to police he had committed approximately 24 acts of arson upon his arrest that New Year's Eve. He also freely admitted these fires had been committed both for his sexual excitement and in the hopes of burning sleeping tramps alive.

As a result of his desertion, Kürten was tried by the military system and convicted of desertion in addition to multiple counts of arson, robbery and attempted robbery (the latter charges pertaining to acts he had also committed that year), and imprisoned from 1905 to 1913. Kürten served his sentence in Münster, with much of his time spent in solitary confinement for repeated instances of insubordination. He would later claim to investigators and Psychologists this period of incarceration was that in which he first encountered severe forms of discipline, and as such, the erotic fantasies he had earlier developed while incarcerated in Derendorf expanded to include graphic fantasies of his striking out at society and killing masses of people; these fantasies became ever more paramount and overbearing in his mind, and Kürten would later claim that he derived the "sort of pleasures from these visions that other people would get from thinking about a naked woman", adding that he would occasionally spontaneously ejaculate while preoccupied with such thoughts.

Further proof of Kürten's awareness was referenced by the premeditated nature of his crimes; his ability to abandon an attack if he sensed a risk of being disturbed; and his acute memory of both his crimes and their chronological detail. Also disclosed in the first week of the trial were the deaths of the two boys whom Kürten had confessed to drowning at the age of nine, with the prosecution suggesting these deaths indicated Kürten had displayed a homicidal propensity dating much earlier than 1913. However, this view was disputed by medical witnesses, who suggested that although indicative of an inherent depravity, these two deaths should not be compared to Kürten's later murders as to a child, the death of a friend can be seen as nothing more than an inconsequential passing.

Released in April 1921, Kürten relocated to Altenburg, where he initially lived with his sister. Through his sister, Kürten became acquainted with a woman three years his senior named Auguste Scharf, a sweet shop proprietor and former prostitute who had previously been convicted of shooting her fiancé to death, and to whom Kürten initially posed as a former prisoner of war. Two years later, Kürten and Scharf married, and although the couple regularly engaged in sex, Kürten later admitted he could consummate his marriage only by fantasising about committing violence against another individual, and that, after their wedding night, he engaged in intercourse with his wife only at her invitation. For the first time in his life, Kürten obtained regular employment, also becoming an active trades union official, although with the exception of his wife, he formed no close friendships. In 1925, he returned with his wife to Düsseldorf, where he soon began affairs with a servant girl named Tiede, and a housemaid named Mech. When his wife discovered his infidelity, Tiede reported Kürten to police, claiming he had seduced her; Mech alleged Kürten had raped her. The more serious charge was later dropped, although Tiede's allegations were pursued, thus earning him an eight-month prison sentence for seduction and threatening behaviour. Kürten served six months of this sentence, with his early release being upon the condition he relocated to Düsseldorf.

Proceedings began with the prosecution formally reciting each of the charges against Kürten, before they recited the formal confession he had provided to police following his arrest. When then asked by the presiding judge to describe why he had continued to commit acts of arson throughout 1929 and 1930, Kürten explained: "When my Desire for injuring people awoke, the love of setting fire to things awoke as well. The sight of the flames excited me, but above all, it was the excitement of the attempts to extinguish the fire and the agitation of those who saw their property being destroyed."

The interviews Kürten granted to Dr. Karl Berg in 1930 and 1931 would prove to be the first psychological study conducted upon a sexual serial killer. These interviews would also form the basis of Berg's book, The Sadist.

Following Kürten's 1931 execution, his head was dissected and mummified; the brain was removed and subjected to forensic analysis in an attempt to explain his personality and behaviour. The examinations of Kürten's brain revealed no abnormalities.

As Kürten awaited his trial, then later as he awaited his execution, he was extensively interviewed by Dr. Karl Berg. In these interviews, Kürten stated to Dr. Berg that his primary motive in committing any form of Criminal activity was one of sexual pleasure, and that he had begun to associate sexual excitement with violent acts and the sight of blood via indulging in both day-dreams and masturbation fantasies — particularly when he had been isolated from human contact. The majority of his assaults and murders had been committed when his wife had been working evenings, and the number of stab or bludgeoning wounds Kürten inflicted upon each victim had varied depending upon the length of time it had taken him to achieve an orgasm. Furthermore, the actual sight of his victim's blood had been integral to his sexual stimulation. Kürten further elaborated to Dr. Berg that once he had committed an attack or murder, the feeling of tension he experienced prior to the commission of the crime would be superseded by one of relief.