Sutcliff was born 14 December 1920 to George Ernest Sutcliff and his wife Nessie Elizabeth, née Lawton, in East Clandon, Surrey. She spent her childhood in Malta and various naval bases where her father, a Royal Navy officer, was stationed. She was affected by Still's disease when she was very young, and used a wheelchair most of her life. Due to her chronic illness, Sutcliff spent most of her time with her mother from whom she learned many of the Celtic and Saxon legends that she would later expand into works of historical fiction. Sutcliff's early schooling was constantly interrupted by moving house and her illness. She did not learn to read until she was nine years of age, and left school at age 14 to enter the Bideford Art School, which she attended for three years, graduating from the General Art Course. Sutcliff then worked as a painter of miniatures.