‘In a moment. First, send a message to Bernadotte. Tell him the Emperor demands an explanation of his conduct yesterday. Marshal Bernadotte is required to justify the fact that his corps did not fire a single shot in anger yesterday when the rest of the Grand Army was inflicting a great defeat on the Prussians.’

The Grand Army set off in pursuit of the enemy later the same morning. Murat’s cavalry led the way, followed by the columns of Ney and Soult. The shattered men of Davout’s and Lannes’s corps were permitted a day’s recuperation before they had to march swiftly to catch up with an advance column that had set off round the flank of the retreating Prussians in order to cut them off from Berlin.The only men fresh enough to lead the flanking force were those of Bernadotte’s corps and Napoleon reluctantly handed him the responsibility for the task. So it was over a week later before Napoleon finally caught up with the advance column and rode into Bernadotte’s headquarters. He swiftly dispensed with any formal greetings and offers of hospitality and demanded an interview with Bernadotte alone. As soon as the other officers had cleared out of the marshal’s office and closed the doors behind them, Napoleon took off his mud-stained cloak and tossed it one of the ornate couches that Bernadotte took with him on campaign, eased himself into the marshal’s chair and for a moment stared hard at his subordinate.

Bernadotte stood stiffly, hands clasped behind his back, head slightly aloof and gleaming boots shoulder width apart. He was clean shaven and his uniform was spotless. It was dark outside and the room was lit by the candles burning in several gilded candelabras. Despite the heat of the fire in the grate and the comforting hue of the candlelight there was no warmth between the two men. Bernadotte returned the Emperor’s hostile gaze unflinchingly.

‘I assume this is about your request for an explanation of my actions at the recent battle, sire.’

‘No,’ Napoleon replied flatly. ‘I seek an explanation of your inaction. And I don’t request it, Marshal Bernadotte. I demand it. Why did you disobey Davout’s instruction to come to his aid?’

Bernadotte smiled faintly.‘I am of the same rank as Davout. I am not obliged to obey his instructions.’

‘Yet I specifically directed you to take orders from him.’

‘A direction is not an order, sire. In any case, I was already obeying your orders in advancing towards Dornburg.’

‘That was written the previous day,’ Napoleon snapped back. ‘And it was superseded by the order to obey Davout.’

‘The order did not reach me until after I had set out for Dornburg.’

‘You dissemble, Marshal. Only your advance elements had begun to march.The rest of your corps had not even left their encampment.’