She is a former editor of History Today magazine, a research fellow at the Institute of Historical Research of the School of Advanced Study at the University of London, and an honorary fellow at the Institute for Advanced Studies in the Humanities and at the University of Edinburgh.
At the age of two she was adopted by a Hemel Hempstead sanitary inspector called Charles Wells and his wife Dolly.
[3] Her books include Wartime: Britain 1939-1945 (Headline, 2004) which recounts the history of the Home Front during World War II.
She acted as historical consultant to the film of Atonement, and is a frequent broadcaster on radio and television, a reviewer and a contributor to the national press, including The Sunday Times, Sunday Telegraph, Financial Times, The Guardian and BBC History.
[6] On 18 February 1961, she married George Gardiner, a British Conservative Party politician and journalist.