The Battle of Eckmühl fought on 22 April 1809, was the turning point of the 1809 Campaign, also known as the War of the Fifth Coalition. Napoleon I had been unprepared for the start of hostilities on 10 April 1809, by the Austrians under Archduke Charles of Austria and for the first time since assuming the French Imperial Crown had been forced to give up the strategic initiative to an opponent. Thanks to the dogged defense waged by the III Corps, commanded by Marshal Davout, and the Bavarian VII Corps, commanded by Marshal Lefebvre, Napoleon was able to defeat the principal Austrian army and wrest the strategic initiative for the remainder of the war.

Louis-Nicolas d'Avout, better known as Davout, 1st Prince of Eckmühl, 1st Duke of Auerstaedt, was a French military commander and Marshal of the Empire who served during both the French Revolutionary Wars and the Napoleonic Wars. His talent for war, along with his reputation as a stern disciplinarian, earned him the nickname "The Iron Marshal". He is ranked along with Marshals André Masséna and Jean Lannes as one of Napoleon's finest commanders. His loyalty and obedience to Napoleon were absolute. During his lifetime, Davout's name was commonly spelled Davoust - this spelling appears on the Arc de Triomphe and in much of the correspondence between Napoleon and his generals.