Andrew Roberts describes (in Napoleon: A Life) the hard fought Battle of Marengo:
The French refused to abandon the Fontanone line when the Austrians counter-attacked; soldiers urinated on muskets that had become too hot to handle from the constant firing.
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‘Bonaparte advanced in front,’ recalled Petit, ‘and exhorted to courage and firmness all the corps he met with; it was visible that his presence reanimated them.’
At this point the Austrian Archduke Joseph, Archduke Charles’s younger brother, crossed the Fontanone with his infantry – the sides were too steep for cavalry or artillery. The French failed to dislodge him and his men started building a trestle bridge, covered by artillery firing canister shot which flayed the French brigade sent to stop them. By 2 p.m. Marengo had fallen: the Austrians had brought eighty guns into play, the Fontanone was being crossed everywhere and Gardanne’s division was broken, fleeing the field, though not before it had bought Napoleon 3 ½ hours’ respite with which to organize his counter-attack. Only Kellermann’s cavalry brigade, carefully retiring squadron by squadron, intimidated the Austrians from releasing their numerically superior cavalry force.
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By this point the Austrians were taunting the French, twirling the bearskins of dead French grenadiers around on their sabres.
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Napoleon, who now had only Monnier’s division and the Consular Guard in reserve, had sent desperate word to Desaix at 11 a.m. to return with Boudet’s division as quickly as possible. ‘I had thought to attack the enemy, instead it is he who has attacked me,’ went his message; ‘in the name of God, come back if you still can!’
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The French moved backwards in good order, one battalion at a time, fighting as they went. It was an utter test of discipline not to succumb to the temptation to break ranks under those circumstances, and it paid off. The day continued very hot, with no water, little artillery support, and sustained attacks from the Austrian cavalry, but some units retreated steadily from 9.30 a.m. to about 4 p.m. over 5 miles, never breaking ranks.
Napoleon calmly called out encouragement and exuded leadership ‘with his accustomed sangfroid’, in the words of one of his guards, ensuring that his infantry, cavalry and paltry artillery each supported one another.
‘The Consul seemed to brave death,’ recalled Petit, ‘and to be near it, for the bullets were seen more than once to drive up the ground between his horse’s legs.’
He had now completely used up his reserves, had barely 6,000 infantry across a 5-mile front, with 1,000 cavalry and only 6 usable guns, and his army was exhausted, desperately thirsty, low on ammunition and one-third hors de combat, but he behaved as if victory were certain.
He even managed to be light-hearted; noticing that the horse Marbot was riding was slightly wounded in the leg, he ‘took me by the ear and said, laughing, “You expect me to lend you my horses for you to treat them in this way?”
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‘We have gone back far enough today,’ Napoleon harangued his men. ‘Soldiers, remember it is my custom to bivouac on the field of battle!’
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When the Austrians came forward at 5 p.m., the front of their centre regiments were ripped apart by canister fire from Marmont’s battery. As at Rivoli, a lucky shot hit an ammunition wagon that exploded and caused chaos. The Austrians recoiled sharply and the shock effect was serious, especially once Boudet’s division advanced upon them. Aggressive Austrian charges soon threw Boudet on the defensive, but just as nearly 6,000 Austrian infantry fired a musket volley and then charged with their bayonets, Kellermann unleashed his cavalry, which had moved up concealed by vines in the trees.
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The French army then advanced across the whole front. It was at this triumphant moment that Desaix was struck in the chest and killed. ‘Why am I not allowed to weep?’ a grief-stricken Napoleon said on being told the news, but he had to concentrate on directing the next assault.
Kellermann’s next attacks sent Austrian cavalry charging back into their own infantry, completely disorganizing them and giving Lannes, Monnier and the Consular Guard the chance to complete the victory by moving forward on all fronts. ‘The fate of a battle is the result of a single instant – a thought,’ Napoleon was later to say about Marengo. ‘The decisive moment comes, a moral spark is lit, and the smallest reserve accomplishes victory.’
Austrian troops who had fought bravely all day simply cracked under the shock and strain of seeing victory snatched from them, and fled back to Alessandria in disorder.
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When the news of Marengo reached Paris, government bonds that had been standing at 11 francs six months earlier, and 29 just before the battle, shot up to 35 francs.
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Napoleon had worked his three arms of infantry, artillery and cavalry together perfectly at Marengo, but it was still a very lucky victory, won largely by the shock value of Desaix’s arrival on the field at precisely the right psychological moment, and Kellermann’s superbly timed cavalry charges. The French reconquered a plain in one hour that it had taken the Austrians eight to occupy. The conscript French troops, guided by the veterans, had acquitted themselves very well.
‘After a great battle,’ wrote Captain Blaze, ‘there is plenty of food for the crows and the bulletin-writers.’
Napoleon had made three major errors: in going onto the plain in the first place, in not anticipating Melas’s attack and in sending Desaix so far away.
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Napoleon also invented some last words for Desaix: ‘Go tell the First Consul that I die with the regret of having not done enough to live in posterity.’ (In fact he had died instantaneously.)
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The view of Desaix’s aide-de-camp Anne-Jean-Marie-René Savary was that ‘If General Desaix had delayed an hour in arriving, we’d have been driven into the Po.’
The day after the battle, Napoleon wrote to the other consuls that he was ‘in the deepest pain over the death of the man I loved and respected the most’.
He took Savary and Desaix’s other aide-de-camp, Jean Rapp, onto his staff as a sign of respect, and he allowed the 9th Légère, which Desaix had been leading when he was killed, to sew the word ‘Incomparable’ in gold onto their standard.
He had Desaix’s corpse embalmed, and a medal struck in his honour, as well as one commemorating Marengo.
All that he said to Kellermann after the battle was, ‘You made a pretty good charge,’ which infuriated him, especially as he had gushed to Bessières, ‘The Guard cavalry covered itself with glory today.’
(Kellermann is supposed to have replied in anger, ‘I’m glad you are satisfied, general, for it has placed the crown on your head’, but it is doubtful that he really did.
Privately, Napoleon admitted to Bourrienne that Kellermann had ‘made a lucky charge. He did it just at the right moment. We are much indebted to him. You see what trifling circumstances decide these affairs.’
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Perhaps the best summing up of the battle was Napoleon’s terse statement to Brune and Dumas: ‘You see, there were two battles on the same day; I lost the first; I gained the second.’
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On June 16 Napoleon offered Emperor Francis peace once again, on the same basis as Campo Formio, writing: ‘I exhort Your Majesty to listen to the cry of humanity.’ In his Order of the Day he claimed the Austrians had recognized ‘that we are only fighting each other so that the English can sell their sugar and coffee at a higher price’.