There was a sudden shout from one side of the square and the two officers turned to see what was happening. One of the grenadier companies had broken ranks and was running away from a tall house that overlooked the market. On the roof Napoleon could see a handful of men throwing tiles down on the French soldiers. Three men were already down and as Napoleon watched another tile thudded into the shoulder of a fourth man, and he collapsed with a sharp cry of agony.

‘Don’t just stand there!’ Colonel Lannes bellowed. ‘Shoot the bastards!’

Musket fire crackled in the square and the tiles around the men on the roof exploded into fragments. They hurriedly ducked back out of sight and after a few more shots the grenadiers lowered their weapons.

‘Find those men,’ ordered Napoleon. ‘They can join the prisoners.’>

Within moments the company that Lannes led down either side of the buildings that the men had fled across came under bombardment from more roof tiles. The example had been set and soon more of the townspeople were on the roofs, raining tiles down on the French soldiers. Napoleon watched with growing frustration as the injured men were carried back into the square. Meanwhile Bourrienne and the colour party had found a clear route through the streets to join their general, and the secretary looked round in shock at the number of men lying on the paving stones having their wounds dressed before he approached Napoleon.

Napoleon nodded a greeting and shook his head wearily. ‘Christ, I hate fighting civilians. Reminds me of the time we had to put down that rebellion in Lyons.’

Bourrienne nodded at the memory of the first action that he and Napoleon had shared as junior lieutenants in the Régiment de la Fère. Napoleon took off his hat and mopped his brow. ‘For most of them it’s just some kind of game. They’ll hurl insults at soldiers one day, rocks the next, and the moment we open fire they cry “massacre” and accuse us of committing some kind of atrocity.’ Napoleon replaced his hat and gave it an extra push to fix it on his head, as if that might protect him from a stray tile. ‘They’re costing me too many men. It’s time the Italians were taught a lesson. We can’t afford to have this mess repeated in every major town behind our lines.’

He turned to a sergeant. ‘Find Colonel Lannes. Tell him that every time a tile is thrown at his men they are to break into the house concerned and kill everyone inside and then torch the place.’

The sergeant smiled cruelly, saluted, and then turned to trot across the piazza, following the sounds of musket fire. Bourrienne looked at his general warily.

‘Is that wise?’ he asked softly.

‘Wise?’ Napoleon shrugged. ‘I think so. Why? What are you thinking?’