At the age of 10 she was engaged to Feren Nadasdy as a political arrangement, though because of her higher social status, she refused to change her last name, and he assumed the name Báthory. The couple married in 1575, when she was 15, and he was 19.
Nadasdy’s wedding gift to Báthory was not only his household of Castle of Csejte, but also a torture chamber built to her specifications.
It is said that the Countess’s initial victims were servant girls, between the ages of 10-14, and daughters of the lesser gentry who were sent to Báthory’s gynaeceum to learn courtly etiquette. There, she would conduct severe beatings, burnings, mutilation of hands, biting the flesh from faces, arms and other body parts, and froze and starved the girls to death. Báthory’s torture included jamming pins and needles under the fingernails of her servant girls, and tying them down, smearing them with honey, and leaving them to be attacked by bees and ants. Testimonies also described her bathing in the blood of virgins to retain their youth (however, this was recorded after her death, so it cannot be verified). According to the Budapest City Archives, she also burned women with hot tongs and then forced them into freezing water.
Although the count participated in his wife’s cruelties, he may have also restrained her impulses; when he died in 1604, she became even more depraved, targeting the daughters of local nobles.
Between 1602 and 1604, rumours of Báthory’s atrocities began to spread throughout the kingdom. Finally, in 1610, King Matthias II assigned Gyorgy Thurzó to investigate. Imprisoned, mutilated, and dead women were discovered in the castle at the time of her arrest.