Half an hour later Napoleon, together with Berthier and a squadron of Guard cavalry, rode into the main battery to meet the enemy deputation. On either side the line of twelve-pounders stretched out across the Austrian countryside. Fifty yards behind them lay the caissons, loaded with powder and shot, ready to feed the guns when they opened fire on Vienna. The gun crews had completed their preparations and stood close by their weapons, watching the Austrians curiously. At Napoleon’s approach the gunners cheered and he indulged it a moment as he slowed his mount to a slow walk and fixed the Austrians with a hard stare. They removed their hats and bowed their heads curtly as the French Emperor raised a hand to quieten his men. Once the cheers had died away Napoleon cleared his throat and addressed the man at the head of the Austrian deputation. The official was tall and thin, and his dark curls were streaked with grey. His coat was finely embroidered with gold lace and a broad red ribbon hung across his shoulder. Napoleon spoke curtly.

‘What is the purpose of your presence here?’

‘Sire, I represent the mayor of Vienna. His honour respectfully requests an audience with you.’

‘Your name?’

‘Baron Karinsky, sire.’

‘Tell me what your master wants.’

‘Yes, sire. He wishes to discuss terms for the surrender of Vienna.’

‘Vienna? I see.’ Napoleon paused. ‘And has Emperor Francis agreed to the surrender of his capital?’

‘As far as I understand, sire.’

‘What does that mean?’

‘His imperial majesty and the court have left the city, sire. The mayor was left in charge with orders to defend it for as long as is practicable.’

‘Then this offer relates to Vienna alone?’ asked Berthier.

‘Indeed, sir.’

‘There is no intention on the part of Emperor Francis to discuss an armistice?’

‘Not as far as I am aware.’

Berthier exchanged a look with Napoleon, who let out a brief sigh of frustration before he continued addressing Karinsky.

‘So why is the mayor preparing to discuss surrender before we have fired a single shot?’

The Austrian gestured towards the city. ‘The garrison has already withdrawn from the walls, sire. On the orders of Archduke Charles. All that remains is the militia. Accordingly, the mayor has determined that he cannot defend the city. Out of compassion for the inhabitants of Vienna he believes it would be better to surrender rather than waste lives in a pointless attempt to resist you, sire.’

‘Where is the garrison now?’ Napoleon snapped.

‘They have retreated across the Danube.’

Napoleon stared at the man briefly. ‘And the bridges are intact?’

The man lowered his eyes as he replied. ‘They were when I left the city, sire.’

Napoleon turned to Berthier. ‘Send a cavalry division forward. Tell Bessières I want his men to take those bridges at once. We must have access to the far bank if we are to—’