Maria Monk (1816?-1849) was a Canadian woman who claimed to have been a nun who had been sexually exploited in her convent.

Maria Monk's book Awful Disclosures of Maria Monk, or, The Hidden Secrets of a Nun's Life in a Convent Exposed was published in January 1836. In it, Monk claimed that nuns of the Sisters of Charity of a Montreal convent of Hotel Dieu were forced to have sex with the priests in the seminary next door. The priests supposedly entered the convent through a secret tunnel. If the sexual union produced a baby, it was baptized and then strangled and dumped into a lime pit in the basement. Uncooperative nuns disappeared.

There is some evidence that Maria Monk suffered a brain injury as a child. One result of this brain injury was that Monk became easily manipulated, and was not able to distinguish between fact and fantasy. It has been suggested that Monk was manipulated into playing a role for profit by her publisher or her ghost writers.

Maria Monk's book came shortly after an earlier incident in Boston, Massachusetts prompted by an anti-Catholic book. In 1835 Rebecca Reed wrote a book called Six Months in a Convent, which contained an unsympathetic, but mostly accurate, description of her experiences in an Ursuline convent school in Charlestown, Massachusetts. This convent was burnt down by a mob shortly before the Reed book appeared, after an incident in which one of the nuns attempted to escape and was persuaded to return, and a rumor circulated that she was being held against her will. Reed died shortly after the publication of her book, of tuberculosis that was widely believed to have been caused by the austerities she practised in the convent.

Reed's book became a best-seller, and Monk or her handlers hoped to cash in on the evident market for anti-Catholic horror fiction by their offering. The tale of Maria Monk was, in fact, clearly modelled on the gothic novels that were popular in the early nineteenth century, a literary genre that had already been used for anti-Catholic sentiments in works such as Matthew Lewis's The Monk. It contains the genre-defining elements of a young, innocent woman being trapped in a remote, old, and gloomily picturesque estate; she learns the dark secrets the place contains, and after harrowing adventures makes her escape.

Monk claimed that she had lived in the convent for seven years, got pregnant and fled because she did not want her baby destroyed. She had told her story to a protestant minister in New York, who had encouraged her to tell her tale to a wider audience. According to Protestant newspaper American Protestant Vindicator, by July 1836 it has sold 26.000 copies. Later other publishers also published books that supported its claims or were close imitators - not to mention tracks that refuted the tale.

The book caused a public outcry. Protestants in Montreal demanded an investigation and the local bishop organized one. Inquiry found no evidence to support the claims but many American Protestants refused to accept the result and accused the bishop of cover-up.

Colonel William Leet Stone, Protestant New York City newspaper editor acquired a permission to set up his own investigation. In October 1836 his team entered the convent and found that the descriptions in the book did not even match the convent interior. During their first visit they were denied entry to the basement and the nuns' personal quarters. Stone returned to New York and interviewed Monk and came to a conclusion that she had never been in the convent. In the later visit he was given the total access to all quarters. Stone's team found no evidence that Maria Monk had even lived in the convent.

Maria Monk disappeared from the public view. It was later rumored that she was actually a Montreal prostitute and had spent the seven years in Magdalen Asylum for Wayward Girls. Many details of the story could have been from her legal guardian William K. Hoyte, an anti-catholic activist and his associates. The writers later sued each other for the share of the profits.

As for Maria Monk, she ran away to Philadelphia with a lover. She penned a sequel, Further Disclosures of Maria Monk, which added nothing to her tale. When she gave birth to a baby in 1838, most of her supporters abandoned her. He was later arrested for pickpocketing and died in Welfare Island, New York City in 1849.

However, the book Awful Disclosures remained in print for years afterwards in various formats and sold well into the 1970's.

Some Protestant circles seem to claim that in the light of recent revelations about clerical sexual abuse and mistreatment of children in some religious schools in Canada and elsewhere, her tale should be re-examined.