Overview
Margaret White (née Brigham) is a fictional character created by American author Stephen King in his first published horror novel, Carrie (1974), where she is the main antagonist.
Margaret is an abusive mother to her daughter Carrie, who eventually pushes Carrie beyond her limits. She is a delusional and mentally unstable religious fanatic, who believes almost everything is a sin to God, especially when related to female anatomy or sexual intercourse.
Novel
In the novel, Margaret is an overweight, unattractive Christian woman who always dresses in shapeless black clothing. She works full-time at a laundromat and has held her job for many years. She often maims herself, or uses various other ways to harm herself, during times of great stress. Once, her daughter Carrie dreamed that Margaret had given herself a hysterectomy after battling the Devil.
She was born Margaret Brigham. Her father was killed in a gun battle and she began attending a fundamentalist church group to deal with the loss, quickly becoming a religious fanatic. Her mother remarried a man named Harold Allison, but Margaret denounced them, believing that they were living in sin.
From Wikipedia (CC BY-SA 4.0).