- Mar 1 Peter Barlow, English mathematician, dies at 85
- Mar 2 Frederick West Lander, American Union brigadier general and poet, dies at 40
- Mar 7 Ben McCulloch, American Brigadier General (Confederate Army), killed in Battle of Pea Ridge, in Arkansas 50
- Mar 7 James McIntosh, American general (Confederate Army), killed in Battle of Pea Ridge, in Arkansas at 32
- Mar 7 William Slack, US Confederate brigadier general, dies in battle
- Mar 8 Adrien de La Fage, composer, dies at 56
- Mar 17 Fromental Halévy, French composer, dies at 62
- Mar 19 Friedrich Wilhelm von Schadow, German painter (Modern Vasari), dies at 73
- Mar 23 Karl Robert von Nesselrode, German-Russian chancellor, dies at 81
Assassination
Car Crash
Hanging
Killed in Action
Plane Crash
Poisoning