Magdalena Rudenschöld (born 1766, died 1823) was a woman in Swedish history, who lived a turbulent life. As a young woman she was employed at the Swedish court and got to know the king of that time, Gustaf III, and she became the mistress of one of his closest deputies, Gustaf Mauritz Armfelt. After the killing of Gustaf III, a temporary government was formed. This was a regency that was put there on behalf of Prince Gustaf Adolf, since he was not yet of age to run the country. The commission to conduct this temporary government was given to Duke Carl, who was the dead king’s brother. King Gustavus III’s former employees and Officers were after the king’s death, opposed by the temporary government, and they were moved to other assignations. Among these former employees and Officers a discontent arose and a few of them, among others Rudenschöld and her friend Armfelt, started to discuss and plan for a change in the governance of Sweden. The planning was mostly done through correspondence. Several of those who took part in this correspondence, was later sentenced for trying to overthrow the Swedish government. One of the sentenced people was Magdalena Rudenschöld. The purpose of this treatise, has been to examine the role and actions of Magdalena Rudenschöld in the Armfelt conspiracy and also to compare the court records to the sentence she received. Rudenschöld was convicted of treason against the king and kingdom. The results show that Rudenschöld’s conviction for being part of treason against king and kingdom was correct, and that she had made no attempt to stop the conspiracy plans. On her part she had mediated letters between people and she had offered to help, for instance by travelling to Russia to speak for their cause. Rudenschöld’s penalty was hard. She was imprisoned for about two years, after having been publicly pilloried. As she was released from prison, Duke Carl provided her a property on the Swedish island Gotland, and she was not permitted to leave it for still some time. The fact that two members of the temporary government was part of the court that sentenced her, probably contributed to the harsh punishment. However, it has to be born in mind that this was how the judicature was organised at the time being. The treatment of Rudenschöld upset the public at the time of the trials - a lady-in-waiting who were pilloried and ended up in prison was very unusual. The fact that the affair was given characteristics of romanticism as Rudenschöld’s intimacy with the married man Armfelt was made public, and that the affair is even more complicated since the conductor of the temporary government - Duke Carl - previously had been in love with Rudenschöld, makes this story linger for posterity.