He has moved to the open back door to sneak a Silk Cut by the time we get on to his long incubation as a published author. So historical characters are still basically the same people we are they just lived 1,000 years ago.' 'My mother was a history teacher,' he offers by way of explanation of his methods, 'and she brought me up with the idea that we haven't evolved. Iggulden, by contrast, appears anxious only to make it all sound: a) fun, and b) none too onerous. Writers of historical fiction, in my admittedly limited experience, are usually all too keen to stress how much research they do, and how the novelist's imagination is just the icing on the cake of what is, at heart, a serious, meticulous, quasi-academic line of work. There again is that tendency to downplay his achievements – and his sheer stamina (he is a 38-year-old father of four children under nine, plus two dogs, one deaf and one frightened of everything and anything). And then there's the one who really bugs me, James Patterson, who manages 14 new releases – seven hardbacks and seven paperbacks – a year.' 'There are some writers who do an awful lot more. 'I always think I could be more productive,' he confesses. Yet, when I remark on his prodigious rate of output, Iggulden looks sceptical. In 2007, he was the first author ever simultaneously to top the UK's fiction and non-fiction bestsellers' charts. Plus, there has been a children's book about tough faeries, Tollins a novella, Blackwater, for 2006 World Book Day and the title with which his name is most readily associated, The Dangerous Book for Boys, co-authored with his younger brother Hal, which has sold four million copies and spawned a whole industry of spin-offs. The fourth instalment of the latter series, Empire of Silver, is out this month. Since his The Gates of Rome appeared in 2003, he has produced a 400-page-plus historical novel every year – that's four of his 'Emperor' books (about Julius Caesar) and three in his 'Conqueror' series about Genghis Khan – totalling three million in sales.

By anybody's standards, Conn Iggulden is a staggeringly prolific author.

The conqueror series by conn iggulden