Tides of War by Stella Tillyard

For her fictional debut, acclaimed historian Stella Tillyard has chosen to focus on a three-year period from early 1812 to the summer of 1815 – the final third of the Peninsula War and its aftermath. It is a brave act. For while there are few widely-read accounts of the Regency – its politics, economics, social and cultural developments – it is a period that readers and television viewers believe they know well. Jane Austen-meets-Sharpe with a dollop of Vanity Fair. Hovering over everything is the lengthy shadow of Georgette Heyer, whose historical romances bring the period to life through page-turner plots and an encyclopaedic knowledge of changing fashions in gloves.

Tillyard is no Heyer. Nor in fairness is Heyer-style romance her aim. Tides of War, subtitled "a novel of the Peninsula War", is as much portrait as novel. Its enthusiasms are those of the historian not the historical novelist. The plot's many offshoots embrace experiments in blood transfusion, the early history of domestic gas lighting and the origins of the Rothschild banking empire. Unlike Heyer's dexterity with the cut of a pelisse or the springs of a phaeton, these areas of inquiry are more than period colour added to bestow a gloss of authenticity: they contribute to the very fabric of the novel.

Tides of War is a panoramic snapshot of a troubled and troubling instant. It depicts a world on the brink of change, malleable to the determination of inventors and financiers, emerging from the cauldron of a Europe-wide war. As it must have appeared to its contemporaries, this is a much more unsettling vision than that served up in Heyer's novels or a glut of Austen adaptations.

That Tillyard has researched deeply and uses her material with relish is, in her first novel, simultaneously both her strength and her weakness. For the prominence of such incursions of "real" history, and the vividness of its presentation, cast into shadow the novel's central fictional goings-on: the story of newlyweds Harriet Raven and her soldier husband James.

Harriet is a free spirit – a young woman of appealingly unorthodox appearance, with an interest in chemistry and a facility for Shakespearean quotations. James is a broad back destined to wear regimentals. So far, so Heyer. But whereas Heyer's unconventional heroines leap from the page, Harriet is oddly uninvolving. As Tillyard herself comments, "Why did she seem to disappear... just when he needed her most; why was there no seabed within her, no plateau on which he could rest?" Both Harriet and James are too insubstantial to carry a narrative as wide-ranging as Tillyard's, and the laurels of Tides of War fall to fictionalisations of real people – Kitty, Lady Wellington, and Nathan Rothschild.

Ultimately this may be unimportant. Tides of War is elegantly written, with passages of verve and, on occasion, poignancy. It is not on a par with Tillyard's works of biography, but it is only a beginning. Another historical novel is on its way.

Matthew Dennison's 'Empress of Rome: the life of Livia' is published by Quercus