I am a firm believer in the idea that history is driven by personality. So although I write biography of a sort, I wouldn’t describe myself as a biographer. I don’t write people’s lives from birth to death, but use biography as a way in to different aspects of history. I’m interested in why do people think, say, do, particular things at a particular time, and in why one person rather than another comes to the front and shapes events. Nonfiction, unsurprisingly, is full of the same stuff novels are made of – power, money, sex and social climbing. That’s what humans do. They also work, however: stuff novelists rarely write about. But work is what shapes most people’s lives, and my books take account of this.

I became interested in this way of looking at things because of my own history. All my grandparents were poor immigrants from Russia. So when I discovered that what I most enjoyed doing was writing books, I wanted to write about people like them – forced out of their original homes by extreme circumstances, and obliged to make their way in a strange and often hostile world.

Vaguely reading around this topic in one of the London Library’s deep leather armchairs, I chanced on the strange story of I.M.Singer, the inventor of the Singer Sewing Machine: failed actor, itinerant inventor and obsessive womaniser, the father of 24 children (all recognised in his will although only the first two and the last four were legitimate) who began life in Ohio’s Western Reserve and ended up in Paignton, England, in a vast house called The Wigwam where he organised private circuses for the entertainment of his numerous family (one of whom grew up to be a princess). Along the way, Singer and his company revolutionised women’s lives, invented installment-plan buying as a way of marketing expensive household appliances, and applied the mass production techniques originally developed to make interchangeable parts for guns to the manufacture of sewing machines. It was a fabulous tale, and Singer was the kind of character novelists would kill to invent. My writing career was on its way.

I tackled a similarly industrial theme in my most recent book, Ugly Beauty, which is about Helena Rubinstein, Eugéne Schueller of L’Oréal, and the beauty business – another rags-to-riches story that includes toyboys, far right politics and drinks trays bugged by the butler.

But many of the books I’ve written in between these two have been concerned with another longstanding interest of mine – self-deception: people’s capacity to convince themselves a particular thing is happening – magic, say, or freedom – when everyone else can see that what’s really going on is something totally different. My books on the Spiritualists, Harry Houdini and (in The New Women and the Old Men) the early socialists are all about this. The Spiritualists shows how many distinguished nineteenth-century scientists, from Alfred Russel Wallace to William James and William Crookes, were so desperate to believe in scientific proof of the supernatural that they let themselves be taken in by obvious conjuring tricks. The Life and Many Deaths of Harry Houdini, telling how Houdini became a legend by escaping from handcuffs, looks at the history and psychology of magic. And The New Women, by examining the love-lives of such figures as Havelock Ellis, Olive Schreiner, H.G.Wells and Eleanor Marx, shows how if you tell someone often enough that they’re leading the new, free life you’ve designed, and skilfully manipulate guilt and principle, they will believe you even when the life they’re actually leading is as unfree as it could possibly be.

Other books examine other long-standing fascinations, such as the roots of charisma (Houdini again, Sarah Bernhardt in Being Divine) or food, in The People’s Chef.

Click here for a full book list.