Catherine was born in Alexandria and raised a pagan, but converted to Christianity in her late teens. It is said that she visited her contemporary, the Roman Emperor Maximinus Daia, and attempted to convince him of the moral error in persecuting Christians.
She succeeded in converting his wife, the Empress, and many pagan philosophers whom the Emperor sent to dispute with her, all of whom were subsequently martyred. Upon the failure of the Emperor to win Catherine over, he ordered her to be put in prison; and when the people who visited her converted, she was condemned to death on the breaking wheel, an instrument of torture. According to legend, the wheel itself broke when she touched it, so she was beheaded.
SOURCE: WIKIPEDIA http://en.wikipedia.org/wiki/Catherine_of_Alexandria