At this time of year many readers may be about to holiday in Italy. One indispensable item for the journey is Christopher Duggan’s brilliant and monumental The Force of Destiny, which deserves to be the standard history of modern Italy for the foreseeable future. Leave a pair of shoes at home and take Duggan instead.

His chronological starting point, when much of the peninsula was overrun by Napoleonic armies, was unpropitious. Before, and for decades after the Risorgimento, Italy was merely the ‘geographical expression’ which Metternich had spoken of in 1847. The flat plains of the Po may have had good roads, but only two