Frederick Walter Stephen West was born on 29 September 1941 at Bickerton Cottage, Much Marcle, Herefordshire, the first surviving child born to Walter Stephen West (5 July 1914 – 28 March 1992) and Daisy Hannah Hill (20 May 1922 – 6 February 1968). His was a poor family of farm workers, close-knit and mutually protective; his father was a disciplinarian and his mother overprotective.

In 1946, the family moved to Moorcourt Cottage at Moorcourt Farm, where Fred's father worked as a milking herdsman and harvest hand. The cottage had no electricity and the sole source of heat came from a log fireplace. By 1951, Fred's mother had given birth to eight children, six of whom survived, but Fred was always his mother's favourite. He was seen as a mother's boy, and relied mostly on his siblings for companionship.

Classmates recall Fred as scruffy, dim, lethargic, and regularly in trouble. Throughout his life, he remained scarcely literate, but with an aptitude for woodwork and artwork. He left school in December 1956 at age 15, initially working as an unskilled labourer at Moorcourt Farm.

By 1957, Fred and his brother John would socialise at a youth club in nearby Ledbury, though his distinct and guttural Herefordshire accent marked him as a "country bumpkin". He aggressively pestered women and girls, whom he objectified as sources of pleasure to be used as he saw fit, and would abruptly approach and fondle them. When a girl did acquiesce to his advances, she would find his sexual performance unsatisfying, as his primary objective was his own gratification.

In June 1961, Fred's 13-year-old sister, Kitty, told her mother that Fred had been having sex with her since the previous December, and had impregnated her. Arrested the same month, Fred freely admitted to police he had been molesting young girls since his early teens and asked, "Doesn't everybody do it?" He was tried on 9 November at Herefordshire Assizes. Though disgusted by her son's actions, Daisy had been prepared to testify in his defence. Kitty refused to testify and the case collapsed. Much of Fred's family effectively disowned him, his mother banished him from the household, and he moved into the Much Marcle house of his aunt Violet. However, by mid-1962, he had reconciled with his parents, although his relationship with most of his family remained fraught.

Fred became re-acquainted with Catherine ("Rena") Bernadette Costello in September 1962, when he was 21 years old. He had first met Costello—who hailed from Coatbridge, Lanarkshire—at a Much Marcle dance hall in 1960, and dated her for several months before she returned to Scotland. By now, Costello was pregnant by a Pakistani bus driver, and she may have relocated from Glasgow to England due to the stigma of her baby's mixed ancestry. She married Fred in Ledbury on 17 November, the sole guest being Fred's younger brother John. The couple initially lived in Fred's aunt's home, but relocated to Coatbridge, where Fred worked as an ice cream van driver. Rena's daughter, Charmaine, was born in March 1963; to explain the child's mixed ancestry, Rena and Fred claimed that she had suffered a miscarriage and that Charmaine was adopted. Shortly thereafter, the couple relocated to Savoy Street, in the Bridgeton district of Glasgow.

In July 1964, Rena bore Fred a daughter, Anna Marie. The child was born at the couple's Savoy Street home. Both the family nanny, Isa McNeill, and neighbours of the Wests recall Rena as a considerate mother "struggling to bring up two children", although Fred treated the children harshly. He kept the girls in the bottom of a bunk bed with bars fitted to the space between the bunks, caging them in; they were allowed out only when he was at work. Shortly thereafter, the Wests became acquainted with 16-year-old Anne McFall, a friend of McNeill's, who was despondent over the death of her boyfriend in a workplace accident. McFall spent a great deal of time at the Wests' flat.

On 4 November 1965, Fred accidentally ran over and killed a small boy in Glasgow with his van. Although cleared of any wrongdoing by police, Fred feared the hostile reaction and potential reprisals for the accident from the locals, whom he relied upon to make his living. Consequently, in December, he chose to return to Gloucester with Charmaine and Anna Marie, renting a caravan at the Timberland Caravan Park in Bishop's Cleeve. Rena joined him in February 1966, accompanied by both Isa McNeill and Anne McFall, who also moved into Fred's caravan. (McNeill and McFall both hailed from impoverished backgrounds; both hoped to find work in England.) Shortly after the move south, Fred found employment driving a lorry for a local abattoir.

The defence next called a succession of women who claimed to have been attacked or assaulted by a lone male whose physical description matched that of Fred West between 1966 and 1975. These seven women each testified they had recognised their attacker as Fred West when his photograph appeared in the media in 1994. The intention of this testimony was to illustrate to the jury that Fred was capable of abducting, assaulting or attempting to attack women without Rose (although the prosecution had never disputed this fact). Despite this, the physical recollections of several of these women varied greatly.

Fred and Rose West are known to have committed at least 12 murders between 1967 and 1987, although many individuals connected to the case have publicly stated they believe there are several other victims whose bodies have never been found. Prior to his suicide, police had recorded over 108 hours of tape-recorded interviews with Fred, both when he had claimed to have acted alone in the commission of the murders, and when he had attempted to portray Rose as being the more culpable participant. On several occasions, Fred made cryptic hints he had claimed several other victims, although he refused to divulge any further information beyond that one further victim had been 15-year-old Mary Bastholm, whom he had murdered in 1968 and buried on farmland near Bishop's Cleeve. He also claimed to have killed one victim while working on a construction project in Birmingham, and that other bodies had been buried in both Scotland and Herefordshire.

Although Rose's parents forbade their daughter from continuing to date Fred, she defied their wishes, prompting them to visit Gloucestershire social services to explain that their 15-year-old daughter was dating an older man, and that in addition, they had heard rumours Rose had begun to engage in prostitution at his caravan. In response, Rose was placed in a home for troubled teenagers in Cheltenham in August of 1969, and she was only allowed to leave these premises under controlled conditions. Although allowed to return home to visit her parents at weekends, Rose almost invariably used these opportunities to visit Fred.

Police were unable to investigate as to whether any further bodies were buried at this location, as these allotments were concreted across in the 1970s as a section of the M8 motorway expansion.

Police firmly believe the Wests were responsible for further unsolved murders and disappearances. Ten murders had been committed between 1971 and 1979—at least seven of which had been committed for sexual purposes. Following the rash of murders between 1973 and 1975, Fred and Rose are not known to have committed any murders until 1978. One further murder was committed in 1979, followed by an eight-year lull until the murder of their own daughter in 1987. No further murders are known to have been committed before their 1994 arrest. Throughout his formal questioning, Fred confessed to murdering up to 30 people, thus indicating up to 18 additional, undiscovered victims.

Knowing Owens' habits of hitchhiking along the A40 between Cinderford and Tewkesbury, the Wests formulated a plan to abduct her for their shared gratification. Fred later admitted that the specific intent of this abduction was the rape and likely murder of Owens, but that his initial incentive was to determine whether his wife would be willing to at least assist him in an abduction. On 6 December 1972, the couple lured Owens into their vehicle with an apology for their conduct and the offer of a lift home. Initially, Owens believed the Wests had been sincere in their apologies to her and obliged, believing she had simply mistaken their earlier intentions. Rose joined her in the back seat, with the explanation she wanted a "girls' chat" as Fred drove.

From their later investigations, police and forensic experts concluded all the victims found in the cellar at 25 Cromwell Street had been murdered in this location, and that, like Gough, each had been dismembered in this location. Five victims were murdered and buried in the cellar at Cromwell Street between November 1973 and April 1975. The first of these victims, 15-year-old Carol Ann Cooper, was abducted on 10 November 1973. Cooper lived in the Pines Children's Home in Worcester, and was abducted after spending the evening at a cinema with her boyfriend. She had been waiting for a bus in Warndon when she vanished, and was likely dragged into Fred's car, where her face was bound with surgical tape and her arms bound with braiding cloth before she was driven to Cromwell Street. At the Wests' address, Cooper was suspended from the wooden beams of the cellar ceiling before her abuse and murder. As had been the case with Lynda, Cooper either died as a result of strangulation or asphyxiation before her dismembered body was buried in a shallow, cubical grave in the cellar.

Even Fred occasionally became the recipient of Rose's violence. On one occasion in August 1974, Rose chased after Fred with a carving knife in her hand, although Fred was able to slam shut the door of the room into which he had run as Rose plunged at him with the knife, resulting in the knife embedding itself in the door, and three of Rose's fingers sliding down the blade, almost severing them from her hand. In response, Rose calmly wrapped her hand in a towel and said: "Look what you done, fella. You've got to take me to the hospital now."

Following the murder of 18-year-old Juanita Mott in April 1975, Fred concreted over the floor of the entire cellar. He would later convert this section of the household into a bedroom for his oldest children, and he and his wife are not known to have committed any further murders until May 1978, when Fred—either with or without Rose's participation but certainly with her knowledge—murdered an 18-year-old lodger named Shirley Robinson. Robinson had taken lodgings with the Wests in April 1977, and was heavily pregnant with a baby son at the time of her murder. Although Rose—herself pregnant at the time—is known to have initially boasted to neighbours the child Robinson was carrying was her husband's, she soon developed a deep resentment of Robinson, and the motive for her murder is likely to have been the removal of a threat to the stability of the Wests' relationship. Her body was buried in the garden of 25 Cromwell Street, and although extensively dismembered, no restraining devices were found with Robinson's remains, thus making a sexual motive for this murder unlikely. Shortly thereafter, Rose unsuccessfully submitted a claim for maternity benefit in Shirley's name with Gloucester social services. As had earlier been the case with Charmaine and Lynda, Fred and Rose allayed the suspicions of anyone who enquired as to Robinson's whereabouts by claiming she had relocated to live with her father in West Germany.

Charmaine's body was initially stowed in the coal cellar of Midland Road until Fred was released from prison. He would later bury her naked body in the yard close to the back door of the flat, and although he remained Adam Ant he had not dismembered this particular victim, a subsequent autopsy suggested the body had been severed at the hip (although this damage may have been caused by building work Fred conducted at the property in 1976). In addition, several bones—particularly patellae, finger, wrist, toe and ankle bones—were missing from her skeleton, leading to the speculation the missing parts had been retained as keepsakes (this would prove to be a distinctive discovery in all the autopsies of the victims exhumed in 1994).

Prosecution witnesses included Cromwell Street lodgers; victims' relatives; Rose's mother Daisy and sister Glenys; and surviving victims including Anna Marie West, Kathryn Halliday (a former lover of Fred and Rose), Caroline Owens, and a "Miss A" (who had been sexually assaulted at 14 by Fred and Rose in 1977, and who described Rose as the more aggressive perpetrator of the two). Neighbours described Charmaine's 1971 disappearance while Fred was imprisoned, and Rose's Casual indifference to Heather's disappearance.

That evening, having been formally charged with his daughter's murder and questioned as to why police had also discovered a third thigh bone, Fred confessed there were two further sets of human remains in his garden, and agreed to return to Cromwell Street to reveal the locations of both graves; one of whom he named as Shirley Robinson, whom he described as being a former tenant and a lesbian who had been heavily pregnant with his child at the time of her 1978 murder; the other victim he described (incorrectly) as being "Shirley's mate", but either could not or would not elaborate as to her identity. Both sets of remains were discovered on 28 February, and Fred was charged with both murders two days later.

Both Heather and Mae West became the focus of Fred's incestuous sexual attentions after Anna Marie ran away from home at age 15 in 1979 after enduring a particularly severe beating from Rose to her stomach just days after being discharged from hospital for treatment of an ectopic pregnancy. The frequency of the abuse endured by Heather and Mae increased when both girls hit puberty. Fred was both overt and unapologetic in his conduct, and would justify his actions with the simple explanation: "I made you; I can do what I like with you." He would further refer to his intentions to impregnate both his daughters on at least one occasion, and would occasionally force all his children to watch pornography with him. As Heather, Mae and their younger brother Stephen were very close in age, the trio resolved that if their father asked either of the two girls to be alone in a room with him, they would only do so if at least one other member of the trio were present to avoid either girl being raped. In addition, both girls developed a regime whereby they would only shower or undress when their father was either out of the house, or as her sister stood guard at the door. Stephen himself was also informed by his father he would have to have sex with his mother by the age of 17 (although his parents would evict him from their home at age 16).

By the mid-1980s, rumours of Rose's sex life had reached several of the children's classmates, and although the West children had been instructed never to divulge details of their home lives to their peers, Heather did confide to her friends that many of these rumours were true. The father of one of these classmates was a friend of the Wests; as such, word soon reached Fred and Rose that Heather had divulged details of her home life—including details of her mother's promiscuity—to her classmates. Fred was so concerned by these revelations that he began to escort Heather to and from school.

After Heather left school in the middle of 1987, she applied for numerous jobs in an effort to leave Cromwell Street. By June, she had pinned her hopes on escaping the household via obtaining a job as a chalet cleaner at a holiday camp in the seaside town of Torquay, although she would receive notification this application had been unsuccessful on 18 June. In response, she crumpled into tears before her siblings Mae and Stephen. That same evening, her whole family heard Heather sobbing aloud as she attempted to sleep, and according to Mae, she "cried all the way through the night." The following morning, on 19 June, Heather was "back to her usual self, looking miserable, biting her nails and sitting on the couch bouncing back and forth as she sat" as her siblings left the house to go to school.

On 6 August 1992, the police searched the West household on the pretext of searching for stolen property. Although numerous objects of sexual paraphernalia—including 99 pornographic videos of both home-made and commercial nature—were discovered, police did not find the video depicting the rape of Fred's daughter. Nonetheless, the 13-year-old made a full statement through a specially-trained solicitor, describing her father's actions, the fact the sexual abuse had begun when she was 11, and that her mother had been casually indifferent to her plight. All the children in the household were placed in foster care the following day. Medical examinations revealed both physical and sexual abuse. (Journalist and author Howard Sounes has also claimed the younger West children were "afflicted with speech impediments and squints.")

Fred had been working in Stroud at the time; upon hearing of the police's intentions, he assured Stephen he would be home immediately (but he would not arrive home until three hours later). When Fred arrived, he informed his family of his intentions to voluntarily offer a witness statement to police regarding his daughter's whereabouts. Despite Fred's insistence in this statement that Heather had been "alive and well", albeit involved in a drugs cartel, and that the claims he and his wife had made as to Heather being buried beneath the family patio were simply "rubbish", police were unassuaged. In response, Fred abruptly changed tactics, claiming they simply held a grudge against him due to his 1993 acquittal of the rape of his daughter.

Fred's remarkably relaxed, emotionally sterile attitude towards all aspects of his crimes had startled many members of the enquiry team. This had prompted Superintendent John Bennett to seek the assistance of a Criminal Psychologist in order that they obtained an expert opinion as to Fred's state of mind. Through analysing Fred's conduct throughout the extensive 1994 interviews, this Psychologist, Paul Britton, advised Superintendent Bennett that Fred's blasé manner indicated he had committed so many offences over such a long period of time that he was now indifferent to the acts of torture, mutilation and murder. Britton added that although an offender of this nature may come to offend less frequently, he would be unlikely to cease killing altogether.

The initially strict suicide watch having been relaxed, on 1 January 1995 Fred West asphyxiated himself in his cell by wrapping an improvised rope he had constructed from a blanket and tags he had stolen from prison laundry bags around his neck, then binding this device to a door handle and window catchment, and sinking to his knees.

Four young girls similar in age and physical characteristics to those Fred was later charged with murdering in Gloucestershire are known to have disappeared during the time Fred lived in Glasgow—one of whom, Margaret McAvoy, he is known to have been acquainted with. Fred is known to have rented a garden allotment adjacent to the property in which he resided and which he frequently visited, although only a small section of this plot was ever cultivated. To one neighbour, Fred is known to have remarked he used the remainder for "something special", although he refused to elaborate. In addition, much of the supposed cultivation of this allotment occurred in the early hours of the morning.

Shortly after his 17th birthday, Fred purchased a motorcycle, and two months later suffered a fractured skull, a broken arm, and a broken leg in an accident. He was unconscious for seven days and walked with braces for several months; because of this incident, Fred developed an extreme fear of hospitals and became prone to fits of rage. Two years later, he suffered another head injury when a girl he groped on a fire escape outside the Ledbury Youth Club punched him, sending him falling two floors.