Claiborne Fox Jackson was an American politician of the Democratic Party in Missouri. He was elected as the 15th Governor of Missouri, serving from January 3, 1861, until July 31, 1861, when he was forced out by the Unionist majority in the legislature, after planning to force secession of the state.

Nathaniel Lyon was a United States Army officer who was the first Union general to be killed in the American Civil War. He is noted for his actions in Missouri in 1861, at the beginning of the conflict, to forestall secret secessionist plans of the governor Claiborne Jackson.