<P> The Battle of Wilson's Creek, also known as the Battle of Oak Hills, was the first major battle of the Trans - Mississippi Theater of the American Civil War . Fought on August 10, 1861, near Springfield, Missouri, between Federal forces and the Missouri State Guard, it is sometimes called the "Bull Run of the West ." </P> <P> At the beginning of the war, Missouri maintained an officially neutral status . However, its governor, Claiborne Fox Jackson, began to work to bring Missouri out of the Union by purchasing arms from and fighting alongside Confederate troops . The two sides repeatedly skirmished, most notably in the Camp Jackson affair, the Battle of Boonville, and the Battle of Carthage. Jackson's support for secession resulted in his removal by a constitutional convention in July . Jackson refused to accept the maneuver as valid, and continued to act as governor . </P> <P> In early August 1861, Confederates under the command of Brig. Gen. Benjamin McCulloch and Missouri State Guard troops under the command of Maj. Gen. Sterling Price approached Union Brig. Gen. Nathaniel Lyon's Army of the West, which was camped at Springfield . On August 9, both sides formulated plans to attack the other . At about 5: 00 a.m. on August 10, Lyon, in two columns commanded by himself and Col. Franz Sigel, attacked the Confederates on Wilson's Creek about 12 miles (19 km) southwest of Springfield . Confederate cavalry received the first blow and retreated from the high ground, later referred to as "Bloody Hill," and infantry soon rushed up to stabilize their positions . The Confederates attacked the Union forces three times during the day, but failed to break through . When Lyon was killed during the battle and General Thomas William Sweeny wounded, Major Samuel D. Sturgis assumed command of the Union forces . Meanwhile, the Confederates routed Sigel's column south of Skegg's Branch . Following the third Confederate attack, which ended at 11: 00 a.m., the Union withdrew . When Sturgis realized that his men were exhausted and lacking ammunition, he ordered a retreat to Springfield . The Confederates were too disorganized and ill - equipped to pursue the retreating Federal forces . </P> <P> The Confederate victory buoyed Southern sympathizers in Missouri and served as a springboard for a bold thrust north that carried Sterling Price and his Missouri State Guard as far as Lexington . In late October, a convention organized by Jackson met in Neosho and passed out an ordinance of secession . Although the state remained in the Union for the remainder of the war, the Battle of Wilson's Creek effectively gave the Confederates control of southwestern Missouri . Today, the National Park Service operates Wilson's Creek National Battlefield on the site of the original conflict . </P>

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