In 1861, Union Brigadier General Nathaniel Lyon marched through the divided slave state Missouri en route to St. Louis. Lyon was to arrest a state militia unit at Camp Jackson that planned to raid a federal arsenal in the city. Upon capturing the men, Lyon's troops encountered crowds of hostile citizens and, after a gun shot, they fired on the mob, killing at least 28 civilians in what is now known as the Camp Jackson affair, or the St. Louis massacre. In this book, the author describes partisan activities leading to hostilities, promotes awareness about the history of slavery in America, and explores political divisions still evident in American culture. Previously unpublished materials about Governor Claiborne Jackson are included, as well as the role of Montgomery Blair in the fight for Missouri, an analysis of the number of arms in the St. Louis Arsenal and the unknown total number of casualties of the St. Louis massacre.

Nathaniel Lyon (1818–1861) was the first Union general to die in the Civil War. Killed at the Battle of Wilson’s Creek, Missouri, he became the North’s first war hero, famed as the man who saved Missouri for the Union. In Damned Yankee, chosen by Choice as an Outstanding Academic Book in 1991, Christopher Phillips portrays Lyon not as the savior of a border state threatened by secessionist extremists but as an unbalanced, monomaniacal Unionist zealot who purposely—and perhaps unnecessarily—brought war to a fragile state whose populace had voted overwhelmingly to stay out of the conflict. Phillips meticulously examines Lyon’s role in the Camp Jackson affair, his quest to oust the pro-southern governor of Missouri, and his campaign to eliminate the secessionist element in the state. He contends that Lyon’s actions in Missouri in 1861 were congruent with his dogmatic personality and troubled past. Damned Yankee is a complex, often shocking, portrait of one of the most controversial figures of the Civil War and a sobering study of how the faults of men may greatly affect history.