St. Dymphna was a seventh century Irish virgin martyr. She was 15 (in about 620) when she lost her life spurning the incestuous advances of her father who insisted on marrying her to replace her deceased mother. When she learned of his plan, she fled from Ireland to Gheel, Belgium, but he found her there and beheaded her when she would not cooperate with him.

There have been many reports of St. Dymphna miraculously curing the mental, emotional, and neurological afflictions of pilgrims to her burial site in Gheel. Based on these miracles and the story of her martyrdom, she was canonized in 1247 and named patron saint of the mentally ill. Her patronage also extends to incest and rape victims and runaways.

St. Dymphna is most often shown with a sword or lamp in her hand and a restrained devil at her feet. Her feast day is May 15.