Foremost in his mind was the coming confrontation with the Empress Josephine. His heart felt heavy with remorse at what he must do when he returned to Paris. France needed an heir to the throne. Only royal blood would do, since it would make it impossible for rival rulers to deny that a child of Napoleon lacked the breeding required to rule as the equal of any other emperor, king or tsar. Even though the logic of his decision to divorce Josephine was unassailable, still he felt the sour grief of being forced to act contrary to his will. Despite all the infidelities on both sides, and his frequent despair over her profligacy, Napoleon loved her as no other. It was as if their hearts and minds were bound together, and the prospect of her enforced rejection crushed almost any notion of pleasure in his life.

Once the last of the guardsmen had received his award, General Rapp ordered the soldiers to shoulder their muskets and then, as the band struck up, the battalions marched off the parade ground. As the last company passed by the civilian sightseers began to spill out across the parade ground. Napoleon turned to Berthier.

‘How are preparations for the army’s departure progressing?’

‘The last two corps are ready to march. The imperial baggage train is packed and can leave at any time. There’s only one issue to resolve.’ Berthier paused. ‘That’s the sale of surplus supplies, ammunition and equipment we captured from the Austrians.’

‘What’s the problem?’

‘The Austrians refuse to pay the price agreed when we signed the treaty.’

‘What are they saying?’

‘They’ll pay thirty million francs, sire.’

Napoleon shook his head with a dry laugh. ‘Thirty million! They must think me a fool. No, the price is fifty million, as we agreed. If they don’t pay up then tell that fool, Prince Metternich, that we will not leave Vienna until they do.’ Napoleon’s resolve hardened even as he spoke and he thrust a finger into Berthier’s chest. ‘You also tell him that if we are not paid in full by the end of the year then I will regard the treaty as having been broken, and that means war. You tell him that!’

‘Yes, sire. As you wish.’

‘Austrian bastards,’ Napoleon hissed through gritted teeth. ‘They brought this war on themselves. Emperor Francis is in no position to change the peace terms. I will bring them to heel, whatever it takes.’

He turned away and made his way down the steps to head back across the parade ground to his quarters in the palace. As he did so a young man stepped forward from the milling crowd of awed sightseers and strode towards him. Napoleon noticed him at the last moment and drew up with a scowl.

‘What’s this?’

‘Sire,’ the man said, eyes wide and staring.‘I bring you a petition from all Germans.’