Countess Elizabeth Báthory (August 7, 1560 – August 21, 1614), was a Hungarian countess from the renowned Báthory family. The family is famous for defending Hungary against the Ottoman Turks. She is known as the most infamous serial killer in Central European history and is remembered as the "Blood Countess" and as Bloody Lady of ?achtice, after the castle near Tren?ín, in Royal Hungary, present-day Slovakia, where she spent most of her life.

After her husband's death, she and four collaborators were accused of torturing and killing hundreds of girls and young women, with one witness attributing to them over 600 victims. In 1610, she was imprisoned in ?achtice Castle, where she remained in her room bricked in until her death four years later. Since she was a Countess she was never formally tried in court. The Báthory case has inspired many legends, including the false story of the countess bathing in the blood of virginal girls whom she killed in order to retain her youth. Like Wallachia's (now Romania) Vlad ?epes the Impaler, who inspired the creation of Dracula, these stories have led to the modern nicknames of the Blood Countess and Countess Dracula.