Camp Jackson Affair
Coordinates: 38°38′12″N 90°14′12″W / 38.636551°N 90.236721°W
The Camp Jackson affair, was an incident in the American Civil War on 10 May 1861, when Union military forces captured a unit of secessionists at Camp Jackson, outside St. Louis, in the divided slave-state of Missouri.
The newly-appointed Union commander, Brigadier-General Nathaniel Lyon, had learned that the troops in Camp Jackson were planning to raid his arsenal in St. Louis. After capturing the entire unit, he marched them into town in order to parole them. En route, hostile secessionist crowds gathered, and after an accidental gunshot, several days of rioting followed. Pro-slavery locals were particularly angered by the presence in Lyon’s force of many German abolitionists who had fled the failed revolution of 1848. The violence was ended only by imposing martial law.
Lyon's action ensured Union control of Missouri for the rest of the war, but it also deepened the divisions within a state that had originally wanted to remain neutral. The affair was also known as the Camp Jackson massacre.
Missouri was a slave state, and many of its leaders favored secession and joining the Confederacy. However, there were relatively few slaves and slaveowners in Missouri, and only a minority favored secession. Over half the population of St. Louis were immigrants, and most were recent German immigrants, who hated slavery and opposed secession. (Many were "Forty-Eighters" who had been active in the failed revolutions of 1848 in the German states.)
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