Catherine was the youngest daughter of 23, called Euphrosyne (Greek for “joy”) by her family.  She had her first vision of Jesus at 6/7 yrs, and secretly took a vow of chastity.  When Catherine reached puberty, her mother made her dress fashionably in the hope of enticing a suitor.  Catherine repented of her acquiescence and cut off her hair.  In retaliation, her family made her perform menial housework and never left her the time or solitude for her religious meditations.  She was able to bear these trials, she later said, because God taught her how to built a private cell in her soul. 

Eventually, she was commanded by God to work in the world, where she attracted followers, tended plague and leprosy victims, reformed rakes, upbraided popes and other power figures, and helped to broker peace treaties whenever possible. 

While some suspected her of hypocrisy and heckled her, by the time of her death at age 33 (presumably due to her habit of extreme fasting and bodily penance -- often today interpreted as anorexia), she was a respected spiritual leader in Tuscany.

She dictated The Dialogue to her confessor to preserve her visions.