Tenuous Neutrality in Missouri
When the American Civil War began, sympathies in the border state of Missouri were greatly divided. Although many Missourians favored remaining in the Union, Governor Claiborne Jackson was a strong proponent of secession. Despite his secessionist leanings, Jackson declared his support for the Union and affirmed Missouri’s neutrality by agreeing to terms of the Price-Harney Truce on May 12, 1861.
Lyon and Price Fight for Control of Missouri
When President Abraham Lincoln requested 75,000 troops from Missouri to take up arms against the Confederacy, Jackson withdrew his support for neutrality. A subsequent meeting between Jackson and Union Brigadier General Nathaniel Lyon failed to resolve the matter. Instead, Lyon’s Army of the West and the Missouri State Guard, commanded by former Missouri Governor Sterling Price, engaged in a series of minor battles during the summer of 1861 for control of the state.
McCulloch Takes Command of Rebel Forces in Missouri
By mid-June, after the Battle of Boonville, Lyon’s army had driven Price’s forces into the southwestern corner of Missouri, where they received reinforcements from other southern states. Brigadier General Ben McCulloch commanded the newly formed, combined Confederate force.
Lyon Takes the Offensive
Rather than stand by and watch McCulloch’s army continue to grow, Lyon determined to go on the offensive. On August 9, 1861, he led approximately 5,400 Union soldiers out of Springfield, Missouri to assault over 11,000 Rebels encamped near Wilson’s Creek, approximately twelve miles southwest of the city.
August 10, 1861 – Surprise Attack Near Wilson’s Creek
Lyon’s surprise attack, on the morning of August 10, caught the Confederates off guard. The Federals initially drove the Rebels back, but the Southerners eventually formed battle lines and halted the Union advance.
Federals Withdraw Following Lyon’s death
The Confederates launched three counterattacks during the day, but despite being outnumbered over two-to-one, the Federals held their ground. During the battle, Rebels killed Lyon and Major Samuel D. Sturgis took command of the Union army. As the day progressed, the exhausted Federals ran low on ammunition, so Sturgis ordered a retreat to Springfield. The exhausted Rebels did not pursue.
Casualties at the Battle of Wilson’s Creek were fairly even. The Union army suffered approximately 1,300 casualties, including 285 killed. The Confederate army suffered about 1,200 casualties, including 277 killed.
The Confederate victory at the Battle of Wilson’s Creek buoyed secessionist sympathies in Missouri and emboldened the Confederates to launch an offensive to regain control of northern Missouri. Secessionists formed a government and formally joined the Confederate cause, but they failed to garner the support of most Missourians. After Union victories at the Battle of Fredericktown (October 21, 1861) and the Battle of Springfield (October 25, 1861), Jackson, Price, and their unofficial Confederate government abandoned the state.