WHEN I WAS nine my parents went to live in Lancaster, near to a large hospital for the mentally ill that everyone called ‘the asylum’. I remember only too well how astonished I was when I was told that a local man had been sent there because he believed he was Napoleon Bonaparte. Now I discover from the first page of Sudhir Hazareesingh’s book that in 1840 a physician called Esquirol carried out a study showing that most megalomaniacs in France took themselves either for Napoleon or for Jesus Christ. That an unfortunate man in Lancaster during the 1930s should also have believed that he was Napoleon is a sign of the fascination that the French emperor holds for everyone. This fascination is itself an important part of the Napoleonic legend. It explains, at least partly, why since his death on 5 May 1821, every month several books have been published somewhere with him as the subject.