Anna Månsdotter, also known as Yngsjömörderskan (in English: The Yngsjö Murderess), (December 28, 1841 – August 7, 1890) was the last woman to be executed in Sweden. The Yngsjö murder is one of the most famous murder-cases in Swedish history. Together with her son, Per Nilsson, she carried out the murder of his wife Hanna Johansdotter in March 1889.
The circumstances of the murder are not entirely clear, as both Månsdotter and her son gave several different explanations for it. In later years it has been suggested that she carried out the murder alone. During the trial it came to light that she had a sexual relationship with her son, and that this eventually led to the murder. It is believed, that she murdered her daughter-in-law because of jealousy, and that she did this with her son's consent.
Anna Månsdotter had married Nils Nilsson, 13 years her elder, expecting a wealthy future, but they had become poor and afflicted with debts. She had three children, of which only one, her son Per, lived to adulthood. Anna's spouse Nils died in 1883. She had arranged the marriage between Per and Hanna Johansdotter, possibly as a way of prevent the spread of rumours about incest. The marriage was not a happy one. Anna did not move in with her own mother, which had been the initial plan, and Hanna complained to her father that her mother-in-law was the cause of her unhappy marriage. One suggestion is that Hanna had discovered the sexual relationship between her husband and his mother, and that they together murdered her to prevent her from being able to tell anyone. One of many summaries given of the murder was that they beat her with a piece of wood, after which Anna strangled her. They then dressed her and placed her as if she had fallen down the stairs.
Anna Månsdotter confessed to the deed along with her son and both were sentenced to death, but hers was the only execution to be carried out. She became the last woman to be executed in Sweden. Nilsson's death sentence was commuted to life in prison. He was eventually released in 1913 and died of consumption in 1918. Anna Månsdotter was, together with Sofia Maria Ekwall, the most infamous female murderer in 19th century Sweden.