Profile £15.99 pp312

For a few brief weeks in early 1777, James Aitken — alias James Boswell, alias James Hill, alias James Hind and John the Painter — was the most infamous man in England. An impoverished 24-year-old house painter of limited accomplishments but vaulting ambition, he was branded by the press as “villainous”, “diabolical” and an “atrocious offender”. Hundreds attended his trial at Winchester ’s Great Hall, an estimated 20,000 his execution outside Portsmouth naval docks 10 days later. Such was the nature of his crimes that Sir Beaumont Hotham, the judge sentencing him, professed himself at a loss to describe Aitken’s misdeeds.

Strangely, the reason for Hotham’s reticence and the nation’s feverish interest had little to do with the slew of robberies, hold-ups and break-ins that Aitken had committed up and down the country in the previous few years (there wasn’t a county in England, he boasted at one point, in which he hadn’t perpetrated some offence or other). Instead, it was his second, markedly less successful criminal career that sent the country into a tailspin. For, after overhearing a conversation in an Oxford pub in late 1775 about the war with the American colonies, Aitken had hit upon an odd but compelling idea — to undermine the British war effort by burning down its busiest dockyards, so crippling its navy. The fact that his bungled attempts at arson and terror led to little more than the firing of Portsmouth’s rope house and a few Bristol warehouses was immaterial; rewards totalling £2,735 were posted for his capture, rumours of French and Spanish agents abounded, George III is said to have asked for daily updates on the progress of the investigation, and the government passed the American High Treason Bill, which suspended habeas corpus for American combatants.

What is curious about the affair — and it is an idea central to Jessica Warner’s lively and intriguing history, the first to deal in full with this striking episode — is why a man like Aitken should have conceived such an audacious and original plan in the first place. The eighth of 12 children born to an impoverished blacksmith in the slums of Edinburgh old town, Aitken seemed preordained, by both temperament and background, for a life of petty crime. What may have changed him was an odd confluence of circumstances — a stammer, which may have fired in him an ambition to “be above the ordinary”; the early death of his father, which assured him a good education at the charitable school of George Heriot’s Hospital; and a love of books, which may have introduced him to Enlightenment ideas and perhaps made him a radical.

There are a lot of maybes here, and there are a lot more in Warner’s book, as she tries, with sometimes unnecessary impressionistic flourishes, to fill in the gaps left by the scarce documentary evidence. Her central contention, though — that the idea picked up by Aitken in that Oxford pub in 1775 offered this ambitious wanderer a purpose he had previously lacked, plus the possibility of celebrity — is compellingly argued. Certainly, within a few weeks of coming up with the notion, Aitken had embarked on a tour of the country’s dockyards, making sketches and taking notes. A few months later, he even risked a journey to France to try and enlist the support of the American Congress’s representative there, Silas Deane. And when, after his arrest, he found himself in the dock facing the probability of execution, he seemed to approach the proceedings in the manner of one for whom the attention afforded by such a trial and such celebrity was reward enough (he is even said to have smiled when the verdict was read out).

Sadly for Aitken, what fame he achieved was remarkably short-lived. Though his gibbeted body, claims Warner, drew “hordes” of onlookers in the first few weeks after his execution, the public’s attention was soon consumed by another dramatic trial. A couple of books were published; a play about his exploits opened and quickly closed at London’s Haymarket Theatre. But Aitken’s only real legacy was the American High Treason Bill , whose strictures against American nationals who might have been involved in terrorist activity strike a strange and compelling chord today.

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