Perhaps the strangest feature of Britain’s Napoleonic army, at least to modern readers, is the purchase system. A rich man, as long as he had served a minimum period in his rank, could buy promotion. Merit had nothing to do with his advancement, only the availability of cash. The system was grossly unfair and led to great resentment, but it also enabled some soldiers, like Wellesley, the future Duke of Wellington, to rise to high rank early enough in his career to become Britain’s most successful General. The French, of course, promoted purely by merit, yet they were never to defeat Wellington.

There is no such place as Valdelacasa on the River Tagus, nor was there ever a South Essex Regiment, but beyond those inventions the campaign of Talavera happened much as described in the novel. In the account of the battle only the adventures of the South Essex and the capture of the Eagle are fictitious; there was a Dutch Battalion fighting with the French, and I took the liberty of moving them from their position opposite the Spanish fortifications and offered them as a sacrifice to Sharpe and Harper instead. The account of Cuesta’s army, sadly, is true; they did run away on the eve of the battle, frightened by their own volley, and within days General Cuesta was to lead them to total defeat. Talavera was abandoned to the French, who, as Wellesley predicts in the novel, treated the British wounded with kindness and consideration. The ineffectiveness of the Spanish army was more than compensated for by the bravery of the Guérilleros, the Spanish civilian ‘freedom fighters’, who caused Napoleon to liken Spain to a ‘running sore’ on his armies.

Much of the detail in the book is taken from contemporary letters and diaries. Scenes like the growing pile of arms and legs outside the convent in Talavera defy imagination and come straight from eyewitness accounts. In addition to those I drew heavily on the scholarship of Michael Glover’s The Peninsular War, Lady Elizabeth Longford’s Wellington: The Years of the Sword, and the American historian Jac Weller’s Wellington in the Peninsula. To those three authors, and to the kind people of Talavera who showed me the battlefield, I acknowledge a special debt.

Richard Sharpe and Patrick Harper are, sadly, inventions. I hope that today’s Royal Green Jackets, who once marched as the 95th Rifles (and as the Royal American Rifles), will not be ashamed of them or their picaresque adventures that will, eventually, lead them to Waterloo and Napoleon himself.