Napoleon rounded on him and stabbed out a finger.‘That’s enough of that! I need the Tsar for an ally and I will not risk any man here offending him, or his entourage, or even that milksop the King of Prussia. No one is to cause our guests the slightest offence. Is that clear, Marshal Ney?’

‘Yes, sire.’ Ney stiffened his spine. ‘Clear as day.’

‘Good. Don’t forget what I have said.’ Napoleon swept his arm round at the rest of his officers. ‘That goes for everyone.’

Berthier nodded towards the far bank. ‘Sire, they’re coming.’

Turning round, Napoleon could see that several barges had emerged round a bend in the river and were making for the landing stage. The leading barge was gilded about the prow, and the standard of imperial Russia rippled languidly from the bows as the craft struck out across the Niemen towards the French bank.

‘Telescope.’ Napoleon held out his hand and a staff officer hurried forward and handed his master a spyglass. Napoleon snapped it out and raised it to his eye, tracking across the gleaming surface of the river until he found the barges. He saw Alexander in the stern of the leading boat, sitting beside another man in uniform, equally glittering and encrusted with decorations.That had to be the King of Prussia, Napoleon realised with a faint smile. No wonder he looked so dour. He would be more depressed still once he discovered the terms Napoleon was going to demand from the peace agreement with his country. If he was abandoned by Russia the Prussian King would have little choice but to accept the demands that Napoleon intended to set before him. As the boat approached the west bank of the Niemen Napoleon lowered the telescope and handed it back to the officer.

‘Right, everyone in position. Stand to attention and make this look as formal a welcoming ceremony as possible.’

The band of the Imperial Guard struck up with the Russian national anthem as the Tsar’s barge drew up alongside the jetty.The oarsmen had learned their lesson from the previous day and were far more cautious in their approach, and Napoleon could almost sense their relief as the boat gently eased itself into position and was held in place by one man at the bows and another in the stern.The two rulers rose up from their cushioned bench and were helped ashore. The King of Prussia landed first and there was no movement from the French ranks until the Tsar stood upon the jetty.

Then Napoleon nodded to Berthier, who waved a hand towards the nearest gun crew.