Catherine Ann McMullen was born on 27 June 1906 in Tyne Dock, England, UK. She grew up as daugther of Rose and John McMullen, but was the illegitimate daughter of Kate Fawcett, whom she believed to be her older sister, and Alexander Davies, a bigamist. She left school at 13 and, and she began work in service but eventually moved south to Hastings, where she met and Tom Cookson, a local grammar-school master, whom she married on June 1940. She suffered some miscarriages and couldn't have children.

She took up writing as a form of therapy to tackle her depression, and joined Hastings Writers' Group. Her first novel was published in 1950. She wrote almost 100 books, which sold more than 123 million copies, her novels being translated into at least 20 languages. She also wrote books under her childhood name, Katie McMullen, and under the pseudonym Catherine Marchant. After receiving an OBE in 1985, Catherine Cookson was created a Dame of the British Empire in 1993. She was appointed an Honorary Fellow of St Hilda's College, Oxford, in 1997. She passed away on 11 June 1998 in North East. She remained the most borrowed author from public libraries in the UK for 17 years, losing the title only in 2002, four years after her death.