Sylvia Ashton-Warner was born in Stratford, New Zealand. Her parents were Francis Ashton Warner, an English immigrant with an aristocratic heritage but little else, and his wife Margaret Maxwell, a teacher. After her father's health deteriorated, her mother became the sole breadwinner of their large family and they moved frequently for her work at small rural schools. As a child, Sylvia dreamed of becoming a concert pianist. She attended Wellington Girls’ College and Wadestown School before passing the examination to enter Auckland Teachers’ Training College. In 1932, she married Keith Henderson, a fellow student, with whom she had three children. She spent many years teaching Maori children, often using pioneering educational techniques that she later described in her 1963 book Teacher and in her autobiography. Her first novel Spinster (1958), published in England, was listed by Time magazine as one of the top 10 books of the year, and was adapted into the 1961 film Two Loves (also known as The Spinster). Her own life story was adapted for the 1985 biographical film Sylvia! Other novels included Incense to Idols (1960), Bell Call (1965), Greenstone (1966) and Myself (1966). She published three volumes of autobiography beginning with I Passed This Way (1979), which won the 1980 New Zealand Book Award for nonfiction. She was awarded the Order of the British Empire in 1982.