During the wars which followed the French Revolution, France’s armies turned on Britain’s last ally in Italy, the kingdom of Naples. The French chased out the Bourbon royal family and established a republic, governed by scholars and philosophers. It lasted six months before an Army of the Holy Faith, under Cardinal Ruffo, counter-attacked and reduced the republic to a handful of castles in Naples itself. In June 1799 their republican garrisons agreed to surrender when Ruffo promised to save them from his fanatical mob by offering them safe passage to France.

That treaty of surrender was signed and sealed when Admiral Nelson arrived in the bay with his British fleet. The admiral, urged on by Lady Hamilton, objected to the treaty’s generous terms, then seemed to relent, permitting the republicans and their families to evacuate their forts. Once they were disarmed and had climbed aboard the waiting transports, Nelson struck and seized the would-be exiles. Hundreds of Neapolitan rebels now found themselves delivered up to a merciless court.

This book asks whether Nelson was capable of such a betrayal. It makes use of accounts by Cardinal Ruffo, Lady Hamilton and Nelson himself, as well as by many others caught up in those brutal events, to tell the story of the atrocity committed in Naples in the summer of 1799. From all those experiences comes the drama. But to Naples alone belongs the tragedy.

• Nelson's actions at Naples in 1799 caused an enormous scandal at the time. His detractors accused him of treason.
• These events inspired Barry Unsworth’s novel 'Losing Nelson' and Susan Sontag’s 'The Volcano Lover' but it has been more than a hundred years since a history on Nelson's infamous crime.
• Nelson's Victorian biographers, however, hushed it all up, keen to preserve his status as England's hero.