Battle of Aspern-Essling
Lobau, Vienna, Austria
On 21 May, the French made their first major effort to cross the Danube, precipitating the Battle of Aspern-Essling. The Austrians enjoyed a comfortable numerical superiority over the French throughout the battle. On the first day, Charles disposed of 110,000 soldiers against only 31,000 commanded by Napoleon. By the second day, reinforcements had boosted French numbers up to 70,000. It was the first defeat Napoleon suffered in a major set-piece battle, and it caused excitement throughout many parts of Europe because it proved that he could be beaten on the battlefield.