Napoleon felt a surge of relief and joy fill his heart as he lowered the telescope and beamed at Berthier. ‘It’s Ney!’

‘Ney?’ Berthier shook his head. ‘Impossible. The rearguard was cut off. There must have been thousands of Cossacks between Ney and the rest of the army.’

Napoleon’s smile faded.‘That explains why there are so few of them. But come on, we must greet him.’

They hurried down the stairs and out into the street. The stern expressions of the guardsmen preparing to defend the town turned to disbelief and joy when Captain Dubois shouted the news that Ney had survived. Napoleon and Berthier edged round the barricade and hurried across the bridge. They stopped on the far side as the head of the column came into view a short distance away. The men were marching in step, muskets resting on their shoulders: the very picture of military efficiency were it not for the rags holding their boots together. At their head marched Marshal Ney, a musket slung across his shoulder and a scarf wrapped over his feathered hat and tied under his chin. Several days’ growth of red beard covered his jaw and cheeks. Twenty paces from the Emperor he stepped to the side of his men and bellowed, ‘Rearguard! Halt!’

The column stamped forward a pace and stopped.

Ney stared at them a moment and then bellowed, ‘Rearguard! Long live Napoleon! Long live France!’

They echoed his cheer with full throats, and as the echo of their cry died away Ney turned to Napoleon. ‘Permission to return to main column, sire?’

‘Permission granted!’ Napoleon laughed. He strode forward and clasped Ney’s arms. ‘My God, it is a fine thing to see you again. How on earth did you manage it?’

‘A moment, if you please, sire.’ Ney turned back to his column and drew a deep breath. ‘Rearguard . . . Fall out! Get some food and some rest. You’ve earned it!’

The men broke ranks and filed past Napoleon and the two marshals. Despite their bearing as they approached the town Napoleon could clearly see that they were at the end of their endurance. Ravaged by hunger and exhaustion, their eyes were sunken in dark sockets and their cheeks looked pinched as they walked stiffly over the bridge. The guardsmen cheered them as they entered the town, embracing their comrades and shoving their own meagre rations into the newcomers’ hands.

‘Just over nine hundred of them,’ Ney said quietly as they passed by. ‘All that’s left of my corps and those that joined them at Smolensk.’

‘What happened?’ asked Berthier.