Ed Kemper’s Montana Boyhood:

How a California Killer’s Formative Years Unfolded in Helena

A Boy Sent North

In the late summer of 1957, a Los Angeles-area electrician named Edmund Emil Kemper Jr. and his wife, Clarnell, ended a marriage that had never been peaceful. Clarnell packed up her three children, Susan, Edmund III, and Allyn, and returned to the state where she had grown up: Montana. The move placed nine-year-old Edmund Emil Kemper III, a boy who would become known decades later as one of California’s most notorious serial killers, into a household in Helena that would shape much of his adolescence. The formal divorce decree was not entered until September 28, 1961, granted in a Montana court on grounds of mental cruelty, but the practical separation, and the relocation north, had already reordered the family’s life four years earlier (Cheney; “10 Serial Killer Cases with Montana Connections”).

Clarnell Elizabeth Stage, as she was born, was herself a product of the state. She had come into the world on March 17, 1921, in the small ranching community of Winnett, in Petroleum County, and had attended Great Falls High School, where a 1938 yearbook records her ambition to become a secretary (Edmund Kemper Stories, “Young Clarnell Stage”). She had married Edmund Kemper Jr. on November 26, 1942, in Great Falls, and the couple’s early years together were shadowed by his wartime service and, later, his work testing nuclear devices at the Pacific Proving Grounds (Edmund Kemper Stories, “Clarnell Strandberg’s Husbands”). When the marriage finally broke down, it was to Montana, and specifically to Helena, that she brought her children.

The Helena Years

Helena in the late 1950s and early 1960s was a modest capital city, its economy tied to state government, ranching, and the remnants of an older mining economy. Clarnell found work there as a secretary at the First National Bank, supporting her children largely on her own (Edmund Kemper Stories, “Clarnell Strandberg’s Husbands”). It was in this setting that young Kemper, already a physically outsized child who would eventually reach six feet nine inches in adulthood, began to exhibit the disturbing behaviors that biographers and forensic writers have since scrutinized. Multiple accounts describe incidents in which he tortured or killed family pets, including a cat he was later found to have decapitated in the family home (Cheney; Lunde). These episodes occurred, by consistent report, during the Montana years, not before the family’s move.

Clarnell’s personal life in Helena remained unsettled. On February 17, 1962, she married Norman Vincent Turnquist, a Montana-born veteran and plumber, in a union that lasted little more than a year before ending in divorce in June 1963 on grounds of extreme cruelty. Less than a year later, on May 17, 1964, she married a third time, to Harold Magnus Strandberg, a Helena-born tradesman; the ceremony took place across the Idaho line in Wallace, Shoshone County (Edmund Kemper Stories, “Clarnell Strandberg’s Husbands”). Kemper retained his stepfather’s surname on his mother’s behalf even after that marriage, too, later dissolved. Strandberg himself remained a Montanan for the rest of his life; he drowned in a boating accident on Holter Lake, north of Helena, in August 1986, after his small outboard capsized in high wind (Edmund Kemper Stories, “Clarnell Strandberg’s Husbands”).

Cracks in the Foundation

The relationship between Kemper and his mother, by his own later account and by the observations of relatives, deteriorated steadily during these Montana years. Kemper described being made to sleep in a windowless basement room, a detail his father corroborated when he briefly returned to the household in 1958 and, by his own account, put a stop to the arrangement (Britannica). Whether this reflected maternal fear that the boy might harm his sisters, as later reported, or simple household discipline, remains a matter on which the surviving sources do not fully agree, and no single account of it should be treated as definitive.

Family tensions in Montana were not confined to the domestic sphere. At his 1973 murder trial in California, Kemper’s younger sister Allyn testified that while the family was living in Montana, her brother had once fired a .22 rifle in their home, the bullet passing close by her head and lodging in a bookcase; contemporary newspaper coverage of the trial recorded her account, along with Kemper’s reported response, “Oops, I thought it was empty” (Edmund Kemper Stories, “Ed Kemper’s Sister Testifies at Trial”). The same testimony connected Kemper to the killing of the family cat during this period, an act his sister said was later a source of quiet suspicion within the family when a young woman was later found murdered in California.

Not every family memory from this period was so dark. Susan Kemper, the eldest sibling, married Irving R. Swanson in Helena on July 23, 1961, in a ceremony reported at length, in the conventional society-page style of the era, by the Independent Record of Helena; the newspaper noted that the bride’s brother, referred to in the article as “Guy Kemper,” gave her away (Independent Record; Edmund Kemper Stories, “Susan Hughey Kemper’s Wedding”). The clipping is a small but useful artifact: it documents a moment in which the Kemper family, whatever private difficulties it carried, still functioned within the ordinary social rhythms of a Montana capital city.

The Return to California and the First Murders

Kemper’s attachment to his father remained strong throughout the Montana years, and it repeatedly drew him back toward California. In 1962, at age fourteen, he ran away from Helena to rejoin his father in the Los Angeles area, only to discover that his father had remarried and was raising a stepson; within weeks he was sent back to Montana (Edmund Kemper Stories, “Kemper Scared His Father’s New Wife”). A second attempt at reunification, in late 1963, ended similarly, and by Christmas of that year his father delivered him instead to his paternal grandparents’ ranch in North Fork, California, a rural community in Madera County. Kemper’s oldest sister recalled that he returned to Montana for part of the summer of 1964, spending time fishing with family before going back to his grandparents (Edmund Kemper Stories, “‘It Really Sunk In That His Dad Didn’t Want Him…’”). A surviving photograph places him in Helena that August, seated at a meal with his stepfather Strandberg, only days before his return to California (Edmund Kemper Stories, “Shortly Before the Murders”).

That return proved catastrophic. On August 27, 1964, following an argument, the fifteen-year-old Kemper shot and killed his grandmother, Maude Matilda Hughey Kemper, and shortly afterward killed his grandfather, Edmund Emil Kemper Sr., when he returned to the property (Britannica; “10 Serial Killer Cases with Montana Connections”). Kemper was committed to a state hospital in California rather than Montana, where he remained for roughly five years before his release in 1969, a decision that has drawn scrutiny from later writers examining the case (Lunde; Britannica).

Montana Recedes

After his release, Kemper’s ties to Montana loosened considerably, though his mother’s connection to the state persisted through her extended family and her Strandberg surname. Kemper settled instead near his mother, who had by then relocated to Santa Cruz County, California, working at the University of California, Santa Cruz. It was there, beginning in 1972, that he murdered six young women, most of them hitchhikers, in a series of killings that gave rise to his later, well-documented nickname, the “Co-ed Killer.” In April 1973 he killed his mother and, days later, one of her friends, before turning himself in to police in Colorado. He was convicted later that year and sentenced to life imprisonment, a sentence he continues to serve at the California Medical Facility in Vacaville (Britannica; “10 Serial Killer Cases with Montana Connections”).

An Uneasy Regional Footnote

Montana’s connection to Kemper is not one the state has ever claimed with any enthusiasm, and it belongs to a broader, uncomfortable category of cases, alongside that of Gallatin County’s David Meirhofer, in which the region’s history intersects with the emerging science of criminal profiling developed by the Federal Bureau of Investigation during the 1970s (CrimeReads). Kemper himself later cooperated extensively with FBI researchers studying the psychology of serial offenders, work that drew in part on the same Montana adolescence recounted here. For historians of the state, the value of this material lies not in sensational detail but in what it documents soberly: a family’s passage through Helena’s postwar civic and social life, and the private strains that passage did not resolve.

Works Cited

“10 Serial Killer Cases with Montana Connections.” Billings Gazette, 18 Mar. 2016, https://billingsgazette.com/news/crime/collection_c6b69538-f20d-570a-af13-0a55cf7a9dac.html. Accessed 26 Aug. 2026.

“Edmund Kemper.” Encyclopaedia Britannica, Encyclopaedia Britannica, Inc., 27 July 2026, https://www.britannica.com/biography/Edmund-Kemper. Accessed 26 Aug. 2026.

Cheney, Margaret. The Co-Ed Killer. Walker and Company, 1976.

Lunde, Donald T. Murder and Madness. San Francisco Book Company, 1976.

“Category: Montana.” Edmund Kemper Stories, https://edmundkemperstories.com/blog/category/montana/. Accessed 26 Aug. 2026.

“Frontier Town Chapel Scene of Susan Hughey Kemper Irving R. Swanson Wedding.” The Independent Record, Helena, MT, 23 July 1961.

“The Murders in 1970s Montana That Finally Brought the FBI’s Profiling Program Into the Field.” CrimeReads, 2 Aug. 2023, https://crimereads.com/murders-in-1970s-montana-fbi-profiling/. Accessed 26 Aug. 2026.