​The Big Book of Female Killers: Mary Ann Cotton, the Arsenic Queen

Illustration for article titled ​The Big Book of Female Killers: Mary Ann Cotton, the Arsenic Queen

This is the third installment of Lady Killers, a series about female serial killers. Read chapters 1 and 2 here.

Mary Ann Cotton

She's dead and she's rotten

She lies in her bed

with her eyes wide open.

They say Jack the Ripper was England's first serial killer, but that's only because the others have been forgotten for a hundred years.

They weren't glamorous like Jack—murdering prostitutes, slashing arteries, mocking the police by mailing them a kidney. These quieter killers were poor, migratory, humble. They fed their children poison. They were desperate. They wanted life insurance. They were caught. They were women.

There was Sarah Dazely, the "female Bluebeard" who killed multiple husbands. There was Mary Milner, who poisoned her in-laws, and Catherine Wilson, who gave her patients sulphuric acid to drink. And there was a pretty young woman named Mary Ann Cotton who couldn't bear to have anyone standing in her way.


Mary Ann Cotton, née Robson, was born in 1832 to poor teenage parents who moved frequently so that her father, a miner, could find work. Although her father fell down a mining shaft when she was nine, and her little sister died young, Mary Ann would later characterize her early childhood as "days of joy," free of the obligations that would haunt her for the rest of her life: marriage, motherhood, and money.

This freedom ended for Mary Ann once her father died and she had to find work to support the family. But she was a hard, skilled worker; as a teenager, she worked as a Sunday school teacher, a dressmaker, and a maid for a wealthy family. This last job gave Mary Ann a glimpse into economic freedom that changed her forever: as an adult, she was never rich, but she loved to hire cleaning women as her one extravagance. In a world of crushing poverty, rampant sickness, and few personal rights, it makes sense that she took great comfort in the knowledge that every week, a maid would come to her house, get down on her knees, and scrub the floor clean.

When Mary Ann was 19, she married a man named William Mowbray. The ceremony took place 20 miles from her home, possibly because Mary Ann was already pregnant and wanted to avoid a scandal. No family or friends were present. This would be the first of many times Mary Ann stood at the altar pregnant and—except for her lover—entirely alone.

Marriage seemed like a way out of poverty, but marriage to William Mowbray was just another form of destitution. Mowbray took his teenage bride to a shanty town in the southwest of England, where Mary Ann gave birth to four or five children, all of whom died without being registered. (At the end of her life, she couldn't remember the exact number of babies she'd had during this time.) When the Mowbrays finally moved back to the north, it was with one living daughter, Margaret Jane, but she died soon after the move from "scarletina anginosa and exhaustion." If we're looking for early psychological scarring in our woman, we can only imagine the toll that the rough landscape, the seemingly inescapable poverty, and the infant deaths took on her over time.


Or maybe the deaths gave her the sense that children were disposable, that they barely needed names, that they'd all end up in the graveyard soon enough.

Mary Ann and William continued to move so that William could work one rough, poorly paid job after another. He eventually found work on a steamer ship, so the couple moved to a town near the coast. They soon had three more children: Isabella, a second Margaret Jane, and baby John Robert, who died one year later of "diarrhoea." Here, the repetition of names implies a certain disposability, a blurring of personalities. Margaret Jane died in 1860; the second Margaret Jane was born in 1861. It was an odd rebirth.


William was gone at sea for months at a time, and soon enough, Mary Ann took up with a red-haired miner named Joseph Nattrass. They would stay in touch for years: he may have been the love of her twisted life, or just the closest thing to luxury that she'd could find in that town. Either way, he helped change her from passive to active. Before Nattrass, Mary Ann had followed her husband from shanty town to shanty town; after him, she began to take things into her own hands.

When, exactly, did Mary Ann change from someone who watched those around her die to someone who caused those around her to die? Did the killings start as a way to get closer to Nattrass? The one common denominator among her victims—beside the fact that they all died in agony—was convenience. Mary Ann killed when it brought her money, when it lessened her responsibilities, when it enabled her to move ahead in life. And maybe, sometimes, she killed out of rage. Her biographer Tony Whitehead (2000) suggests that she may have "snapped" in 1864, when William was out to sea and she was stuck with the children. Somewhere around this time, she discovered what arsenic could do to the human body. She also figured out how easy it was to mix it into a cup of hot tea.


William died in 1865. His cause of death was listed as "typhus fever and diarrhoea," which doesn't match up with the symptoms of arsenic poisoning, unless the doctor who filled out the death certificate mixed up "typhus" and "typhoid." Typhoid fever did in fact look a lot like arsenic poisoning, while typhus came with a distinct rash, and though the two were clearly different, doctors of the time often used the terms interchangeably, according to biographer David Wilson (2013).

Whether Mary Ann killed William or not, his death was certainly convenient, as it freed her up to pursue Nattrass. She collected a large sum of insurance money and moved with her two young daughters to the town where Nattrass lived. Soon enough, the second Margaret Jane was dead of "typhus fever," like her father, and her sister Isabella was sent off to her grandmother's, which ended up prolonging Isabella's life. She'd live to be nine years old—the oldest of Mary Ann's murdered children.


We don't know whether Mary Ann knew Nattrass was already married when she moved. She may have been disappointed to find out the truth; she may have felt relieved to be free of husband and children for the first time since her childhood. Either way, she moved back to the town she'd come from and took up nursing, which ended up being her best gig yet. (See: feeding people small doses of "medicine," caring for the agonized dying without making anyone suspicious.) During this time, she charmed a patient named George Ward and married him right away.

No one from her family attended the service. The "witness" on the marriage certificate was the groom from the wedding right before theirs. And George ended up being sort of a throwaway husband: the two had no children, she never used his last name once the marriage was over, and she only stayed with him for 15 months. At that point, George died, suffering from the classic symptoms of arsenic poisoning: diarrhea, stomach pains, and a tingling in his hands and feet.


With her second husband out of the way and the majority of her children dead, Mary Ann continued this new, fatal hustle. She moved again, snagging a job as the housekeeper to a wealthy father of five named James Robinson, whose wife had recently died.

Mary Ann moved into the Robinson home right before the Christmas of 1866, and one day later, the youngest Robinson child was dead. This was probably just a coincidence, since the timing is so implausibly dramatic, but if Mary Ann already had her eye on James, maybe the death was a sort of sick love letter: I want you, and I really don't want to take care of your children in the process. All we know is that the baby died of "convulsions," which were often a sign of arsenic poisoning.


The death of his child didn't dampen James Robinson's passions. Mary Ann was pregnant within two months of moving in. But then her mother got sick, and Mary Ann was called away to nurse her. Nine days later, her mother was dead. The neighbors grew suspicious, since "nurse" Mary Ann had both predicted it and informed them that she was claiming certain items of bedding and clothing. But Mary Ann ignored the rumors, snatched up her daughter Isabella, and ran back to James.

April 1867 was a bad month for the Robinson household. Three of the children living there died within 10 days of each other: nine-year-old Isabella, the last Mowbray, died of "gastric fever"; six-year-old James Robinson died of "continued fever"; his eight-year-old sister, Elizabeth, died of "gastric fever." All of these "natural causes" were easy cover-ups for arsenic poisoning. The fact that the deaths came in such quick succession shows us how heavy-handed Mary Ann could be with the poison, and how impatient she was with the requirements of quasi-stepmother-hood—but it also shows us just how common childhood death was during that era. Three children dying back-to-back didn't make anyone suspicious. Life limped on.


James Robinson married his children's murderer in another solitary ceremony sometime during August 1867. Their first daughter was born that November, and she was dead of "convulsions" within months. (Mary Ann used pregnancy as a way to secure marriage, but she wasn't particularly interested in raising her children.) By 1869, James and Mary Ann had another child together, George, and they were beginning to argue about money, as James discovered Mary Ann's habit of minor financial deceptions. She ran up little debts, she kept money that she claimed to have spent, and she enlisted his last surviving son to pawn clothes for her. They fought about this last incident furiously, and Mary Ann moved away, taking baby George. While she was gone, James boarded up the house and moved in with a sister. Later, in a letter, Mary Ann would spin this action as betrayal on his part: "I left the house fore a few days I did not wish to part from him...When I returned ther wos no home for me."

After a few months away, Mary Ann sashayed back into town with baby George and dropped him off at a friend's house in order to "mail a letter." She never returned for the child. Eventually, George was reunited with his father, his mother's abandonment having saved his life.


Now 37 years old, Mary Ann worked and wandered. She was free of husband and children for the third time in her life, but it wasn't long before she jumped back into the fray. She began to correspond with an acquaintance from her younger days—a wealthy spinster named Margaret Cotton. Margaret had a brother, Frederick, who was a widower with two sons and needed a housekeeper. So Mary Ann agreed to take the job.

Mary Ann became Frederick Cotton's housekeeper at the beginning of 1870, and four weeks later, his sister Margaret was dead. Margaret's money went straight to her brother; her brother went straight to Mary Ann, who was soon pregnant. She married Frederick in the fall, despite the fact that she was still technically married to her previous husband, and a few weeks later, she took out life insurance on his sons.


In 1871, the new fivesome moved to West Auckland: Mary Ann, Frederick Cotton, his sons Frederick Junior and Charles Edward, and the new baby, Robert Robson. The move must have been Mary Ann's idea, because conveniently enough, they moved into a house on the same street as a certain red-headed miner from her past. Joseph Nattrass was no longer married, and now Mary Ann had an easy recipe for not having a husband anymore: a little arsenic and a cup of hot tea.

Illustration for article titled ​The Big Book of Female Killers: Mary Ann Cotton, the Arsenic Queen

She was getting reckless. She no longer had time to stay married for years or to let her children celebrate a birthday or two before she snuffed them out. So Frederick Cotton died quickly, and just as quickly, Nattrass moved in with her and the children as a "lodger."

Mary Ann probably intended to marry Nattrass when she killed Frederick. Murder and remarriage had been her modus operandi up to this point, and the move to West Auckland seemed like the final step in achieving her goal—except she had already, remarkably, met a new man, and he was richer than Nattrass. His name was Quick-Manning, and Mary Ann had recently nursed him back to health.


With Quick-Manning in her sights, Mary Ann acted fast. She poisoned Frederick Cotton Jr. ("gastric fever"); killed her baby Robert Robson ("convulsions and teething"); and finally poisoned Nattrass ("typhoid fever")—all within 20 days of each other. A neighbor girl who was present at Nattrass' sickbed described the scene as follows: "I saw him have fits, he was very twisted up and seemed in great agony.... He said, 'It is no fever I have'.... I have seen [Mary Ann] several times give him a drink."

Joseph Nattrass, writhing in bed as his lover gave him poisoned tea: he knew he didn't have the typhoid fever the doctors had identified, but there was nothing he could do. Besides, Mary Ann was eager for Nattrass to die so that she could bury him at the same time as her baby Robert Robson, who'd died four days earlier, and save a little on funeral expenses. So Nattrass convulsed to death, certain that someone was tricking him, with his lover's dead baby laid out in the same room.


Once all that messy business was over, Mary Ann became pregnant by Quick-Manning.

At this point, she had only one other dependent left: her stepson Charles Edward, the last Cotton boy. She resented this. He wasn't even her child. And it was this boy who would become her downfall.


One afternoon, a local grocer and druggist named Thomas Riley stopped by Mary Ann's house to ask if she could nurse another smallpox patient. As they chatted, Mary Ann kept expressing irritation at having to care for a child that wasn't hers. Charles Edward was in the corner of the room, listening. She asked Riley if he could put Charles Edward into the workhouse. Riley said no.

Coolly, Mary Ann replied, "Perhaps it won't matter, as I won't be troubled long. He'll go like all the rest of the Cotton family." Six days later, Charles Edward was dead.


Riley happened to be walking by Mary Ann's house when it happened, and he noticed her standing in the doorway, openly distressed. She told him about the death, and asked him to look at the body. Horrified, Riley went straight to the police.

An inquest was held, and Charles Edward's poor little body was laid out on a table in Mary Ann's house for a postmortem. A sloppy one, mind you: the death was ruled "natural" and Mary Ann went on her way. But the town gossips and local papers had already picked up on Riley's suspicions, and eventually convinced the doctor who'd done the postmortem to investigate the body again.


The doctor analyzed the contents of Charles Edward's stomach, which he'd buried in jars in his yard—as doctors do—and immediately discovered grains of arsenic in the child's viscera. He went to the police station at midnight, and Mary Ann was arrested the next day.

Initially, she was only accused of the murder of Charles Edward. But soon enough the charges ballooned to include Joseph Nattrass, Frederick Cotton Jr. and the baby Robert Robson. Their bodies were exhumed and tested, and huge amounts of arsenic were found in all three. (They tried to exhume Frederick Cotton Sr., but couldn't find his body anywhere, and dug up several graves in the process.)


Mary Ann gave birth to Quick-Manning's child in prison, and during her trial, she'd breast-feed the baby in front of the court, refusing to talk. It was a savvy move, working the jury's sympathies by tapping into Victorian ideals of femininity. How could this silent, breastfeeding mother be capable of murder?

Her defense latched onto the fact that no arsenic had actually been discovered in her house at the time of Charles Edward's death. They argued that Charles Edward had been accidentally poisoned from arsenic fumes rising off the green wallpaper in his bedroom and from flakes of the arsenic-and-soft-soap mixture that Mary Ann used to clean. The prosecution brought in a prestigious doctor, who discounted this theory. There was simply too much poison in the corpses. Joseph Nattrass' body, for example, contained four times the amount of arsenic necessary to kill a man.


The only time Mary Ann broke down was when the defense gave a melodramatic speech about the implausibility of a mother killing her own child. "A mother nursing [her baby]...seeing its pretty smiles, while she knew she had given it arsenic, making its limbs writhe as it looked into her face wanting support and protection!" the defense wailed, and Mary Ann started to cry. Her tears could have been part of her act, but regardless, the defense was describing exactly what Mary Ann had done numerous times, to numerous babies.

Ultimately, Mary Ann was convicted of "the awful crime of murder" for the death of Charles Edward. The judge declared, "You seem to have given way to that most awful of all delusions...that you could carry out your wicked designs without detection." She was sentenced to be hanged.


The hangman chosen to execute Mary Ann Cotton was a controversial figure with several botched executions under his belt. He preferred to use a "short drop" from the platform, which occasionally had the unpleasant side effect of not breaking the prisoner's neck. When this happened, the hangman had to press down on the shoulders of the dying as they slowly strangled, spinning at the end of the rope.

During her final days, Mary Ann wrote frantic letters to family and friends asking them to petition for a reprieve. She continued to insist that she was innocent, and her letters have a martyred, incredulous tone—she liked to complain about the "lyies that has been told A Bout me," and begged her one surviving husband, James Robinson, to visit and bring his surviving children with him. Naturally, he refused. She did make one final, maternal gesture, though: she arranged for her last child to be adopted. "Her parting with it," ran The Burnley Advertiser in March 1873, "was of a most affecting description."


Mary Ann had been a mother, now, for exactly half of her life. Whether she liked it or not, her existence up to this point had been largely defined by being secretly pregnant, or publicly pregnant, or recently pregnant, or pregnant with another man's child. Seduction and, by extension, pregnancy, had been one of her most faithful weapons (the other was a white powder available at the local pharmacy). Mary Ann used her fertility to control the rise and fall of her life. Giving away this last baby was a powerful sign that everything—the seduction, the marriage, the birthing, the poisoning—was very much over.

Was Mary Ann a sociopath, hooked on the power of killing the innocent? Was she a capitalist, climbing the social ladder of husbands in a desperate attempt to gain some autonomy? She was clearly striving for something, but it's unclear what she wanted most. Money? Freedom? Other people's pain? She never stopped moving and plotting, but despite all her frantic action, she only ever spun in circles. She must have seen marriage and motherhood as a form of imprisonment, but every time she broke free, she immediately locked herself up again. She killed one husband only to marry the next; she poisoned one child and soon became pregnant with another. Mary Ann Cotton wanted a different life for herself, but she could never break free from her hall of mirrors, reliving her history time after time.

Illustration for article titled ​The Big Book of Female Killers: Mary Ann Cotton, the Arsenic Queen

Mary Ann walked the four minutes to the scaffold on March, 24, 1873. She was 40 years old, wearing a black and white checked shawl which disguised the fact that her arms were bound to her sides with a belt. A crowd of people gathered outside the jail to catch a glimpse of her. The journalists inside wrote that she looked like "a doomed wretch," sobbing hysterically as she shuffled forward. On the scaffold, she shuddered when the rope went around her neck. Her last words were, "Lord, have mercy on my soul"—and then the ground dropped from under her feet.


It took her three minutes to die, and the executioner had to steady her twitching body with his own hands.

"The announcement of her execution may dispel a popular idea, long too prevalent, to the effect that a female assassin, however frightful her wickedness, may generally hope for a reprieve in consideration of her sex," ran The Burnley Advertiser a few days later. "But the atrocities of Mary Ann Cotton put her beyond the pale of human mercy, for, unless she was fearfully maligned, no more hideous monster ever breathed on earth."


About a week after she died, a moralizing play called "The Life and Death of Mary Ann Cotton" opened. For a while, children sang about her on the street. But soon enough she was forgotten, and birth and death went on as before in the little towns of England.

Illustration by Jim Cooke.

Tori Telfer is a writer from Chicago prone to nightmares, writing about creepers, and snatching ideas for stories from happier dreams. Read more of her work here. Read the first two chapters of Lady Killers here.


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Madeleine Davies

I love this series so much I could scream.