St. Margaret of Antioch
Believed to be a legend, now, Margaret was the daughter of a a pagan priest in Pisidian Antioch, Asia Minor. Her mother died when she was an infant and she was raised a Christian by her nurse. This led to her father disowning her.
She was very beautiful and a Roman prefect, failing to seduce her, denounced her as a Christian during the last general persecution. She was brought to trial and put to death for refusing to sacrifice to pagan gods.
In one story Margaret is supposed to have met the devil in the form of a dragon who swallowed her. A cross she carried, aggravated the dragon so badly it spit her out again. This led to popular depictions of her with dead dragons or leading a dragon on a chain.
She is the patron saint of women, escape from devils, pregnancy and childbirth among other things and she is said to be one of the saints who appeared to St. Joan of Arc.