Nathaniel Lyon

Nathaniel Lyon (1818-1861) was a United States Army officer who was the first Union general to be killed in the American Civil War, dying at the Battle of Wilson's Creek on 10 August 1861 while rallying his outnumbered soldiers. He is noted for his actions in Missouri in 1861 to forestall the secessionist plans of governor Claiborne Jackson, including the Camp Jackson Affair in St. Louis. He had earlier fought in the Second Seminole War and the Mexican-American War, and in 1850 co-led the Bloody Island Massacre of Pomo people in California.

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