In 1571, a fifteen-year-old girl in Leuven fell ill with strange and disturbing symptoms. Katherine Gualter was the daughter of a cooper and was usually in good health, with a temperament that inclined towards an equal mixture of the melancholy and sanguine humours. She had recently started her monthly periods. One day, Katherine ate a cake that had been given to her by a local woman with a bad reputation. She found it painful to swallow and afterwards she complained of strange stomach pains, exhaustion, dizziness, and nausea. Her symptoms suggested that she had been poisoned.