Britain's First Serial Killer's Domestic Method

Long before the phrase “serial killer” existed, Mary Ann Cotton was quietly killing her way across the coalfields of Victorian County Durham, and doing it so patiently, and so plausibly, that for years no one suspected a thing. She is now often called Britain’s first serial killer, and the scale of what she did is staggering: as many as twenty-one people, including her own children, are believed to have died at her hands.

Born in 1832 in a mining village, Mary Ann’s life was one of hardship, and she learned to see the people around her as a means to money. Her method was chillingly domestic. She would marry, or move in, or take in lodgers and children — and then, one by one, they would sicken and die of what the local doctors put down to “gastric fever,” a common and unremarkable killer in the filthy, cramped conditions of the age. What no one realised was that the true cause was arsenic, then cheaply and freely available in soft soap and other household products, which produces symptoms — violent stomach pain, vomiting, diarrhoea — almost identical to the gastric illnesses that killed so many Victorians anyway. And crucially, before nearly every death, Mary Ann had taken out a modest life insurance policy.

The Horror

Over roughly twenty years, an appalling procession of people around Mary Ann Cotton died. She is believed to have killed four husbands, a lover, her own mother, and — most horrifying of all — around eleven of her thirteen children, as well as stepchildren, poisoning them for burial-club and insurance payouts of just a few pounds at a time. She moved from village to village as suspicion never quite caught up with her, a respectable-seeming widow and nurse who buried her dead and moved on. What finally destroyed her was not a brilliant piece of detective work, but her own impatience — and a single sentence. A parish official was arranging the care of her young stepson, Charles Edward Cotton, whom Mary Ann wanted rid of. She complained that the boy was in her way, and said of him: “I won’t be troubled long. He’ll go like all the rest of the Cottons.” Days later, the perfectly healthy little boy was dead. This time, the official remembered her words. A doctor kept samples. And when they were tested, they were found to be full of arsenic.

Mary Ann Cotton was arrested and tried for murder. By now the true, monstrous pattern of her life was becoming clear — the string of dead husbands and children stretching back across the years. She was convicted of the murder of the little boy, Charles Edward, and sentenced to death.

The Modern Relic

On 24 March 1873, she was hanged at Durham Gaol by the notorious, elderly executioner William Calcraft — a man famous for using a “short drop,” which killed not by cleanly breaking the neck but by slow strangulation. Mary Ann Cotton’s end was reportedly exactly that: the rope was too short, her neck did not break, and she is said to have strangled slowly on the rope for around three agonising minutes before she died. The relic she left behind is not a building but something that has outlived her by 150 years: a folk rhyme. In the villages of the North East, children still skip and sing a grim little verse about her — “Mary Ann Cotton, she’s dead and she’s rotten, lying in bed with her eyes wide open…” — a piece of living dark folklore passed down the generations in the very County Durham communities where she once moved from house to house, taking out insurance policies and burying the dead. You can walk those same villages — West Auckland chief among them — where Britain’s first serial killer did her quiet, patient work.

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