The battle of Wagram began on the 5th July, but the issue was not determined until the following day. Macdonald, who played a prominent part in the fighting, as will be narrated, thus describes it in a private letter:--
“The crossing of the Danube [on the 4th and 5th July] was a masterpiece of prodigious genius, and it was reserved for the Emperor to conceive, create, and carry it out. It was performed in presence of an army of over 180,000 men.[2] The enemy expected the attempt to be made at the same point as that of May 21st.[3] They had prepared tremendous entrenchments, and had brought up a formidable body of artillery; but, to their great surprise, they suddenly saw us attack their left flank and turn all the lines of their redoubts. We drove them back three leagues, and when, next day, they tried conclusions with us, they lost the game.
“Never, sir, had two armies a mightier force of artillery, never was battle fought more obstinately. Picture to yourself 1,000 or 1,200 pieces of artillery vomiting forth death upon nearly 350,000 combatants, and you will have an idea of what this hotly-disputed field of battle was like. The enemy, posted upon the heights, entrenched to the teeth in all the villages, formed a sort of crescent, or horse-shoe. The Emperor did not hesitate to enter into the midst of them, and to take up a parallel position.
“His Majesty did me the honour of giving me the command of a corps, with orders to break through the enemy’s centre. I, fortunately, succeeded, notwithstanding the fire of a hundred guns, masses of infantry, and charges of cavalry, led by the Archduke Charles in person. His infantry would never cross bayonets with mine, nor would his cavalry wait till mine came up; the Uhlans alone made a stand, and they were scattered.
“I pursued the enemy closely with bayonet and cannon for about four leagues, and it was only at ten o’clock at night that, worn out and overwhelmed with fatigue, my men ceased their firing and their pursuit.
“The same success attended us at all other points. His Majesty, who directed everything, amazed me by his coolness and by the precision of his orders. It was the first time I had fought under his eyes, and this opportunity gave me an even higher opinion than I already had of his great talents, as I was able to form my own judgment upon them....”