Under Napoleon
He remained without employment until 1809, but then Napoleon made him military adviser to Prince Eugène de Beauharnais, viceroy of the Kingdom of Italy and a corps commander. He led the army from Italy to join with Napoleon, and at Wagram, led the attack which broke the Austrian centre and won the victory.
Napoleon made him a Marshal of France on the field of battle, and soon after created him duke of Taranto in the Kingdom of Naples.
In 1810, MacDonald served in Spain and in 1812, he commanded the left wing of the Grande Armée for the invasion of Russia. In 1813, after participating in the battles of Lützen and Bautzen, he was ordered to invade Silesia, where Blücher defeated him with great loss at Katzbach. At the Battle of Nations in 1813, his force was pushed out at Liebertwolkwitz by Johann von Klenau's IV Corps (Austrian); on a counter attack, his troops took the village back. Later that day, Klenau foiled his attempt to flank the Austrian main army, commanded by Karl Philipp, Prince of Schwarzenberg. After the Battle of Leipzig, he was ordered to cover the evacuation of Leipzig with Prince Poniatowski. After the blowing up of the last bridge over the river, he managed to swim the Elster, but Poniatowski drowned. During the defensive campaign of 1814, MacDonald again distinguished himself. He was one of the marshals sent by Napoleon to take the notice of his abdication to Paris. When all were deserting Napoleon, MacDonald remained faithful. He was directed by Napoleon to give his adherence to the new régime, and was presented with the sabre of Murad Bey for his fidelity. However, it is alleged that Napoleon once said, half-jokingly, that he would "never trust a Macdonald within sound of bagpipes."
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