Date and place
- May 21st and 22nd, 1809 at Lobau, a swampy area near Vienna, Austria.
- French army (90,000 men) under Emperor Napoleon the First.
- Austrian army (75,000 men) under Archduke Charles of Austria, Duke of Teschen.
Casualties and losses
- French army: about 6,000 killed, including Marshall Jean Lannes, 20,000 injured or prisoners.
- Austrian army: over 24,000 men out of combat (killed, injured, prisoners).