On June 17, 1861, the Battle of Boonville was fought along this road and nearby locations in a clash that was more skirmish than full battle but had major consequences for Missouri's place in the Civil War. After months of rising tension between Unionist and Secessionist factions, Governor Claiborne Fox Jackson and Major General Sterling Price sought to build the State Guard into a force that could take Missouri into the Confederacy, while Unionist leaders in St. Louis, including Congressman Frank Blair, Jr. and General Nathaniel Lyon, moved to stop them. Following a June 11 meeting in St. Louis that ended with Lyon declaring that a state of war existed, Jackson and Price abandoned Jefferson City, hoping to hold Boonville long enough for Southern strength to gather at Lexington. Jackson evacuated the capital on June 13, and two days later Lyon and Blair arrived with two thousand soldiers in four boats to seize Jefferson City before Lyon pushed on toward Boonville with seventeen hundred men. Fearing artillery on the bluffs, Lyon landed about eight miles below town, marched inland, and encountered State Guard pickets as his force rose from the Missouri River floodplain onto the Rocheport Road. About four or five hundred State Guardsmen under Colonel John Sappington Marmaduke had taken position near a lane intersection west of the first shots, using a brick house, outbuildings, fences, a wheat field, and nearby woods for cover, although Marmaduke believed his fifteen hundred poorly armed and untrained men could not match Lyon's disciplined and well-equipped troops and had urged a withdrawal to more favorable ground. At about 8 a.m., Lyon's artillery under Captain Totten opened the main action with shelling while infantry advanced on both flanks. After heavy exchange of fire, cannon shot struck the brick house and the Southern line fell back, briefly re-formed near the brow of a hill, and fired again before Federal artillery and flanking pressure drove it into retreat. The fighting lasted little more than twenty minutes, and the Southern withdrawal soon dissolved into disorder. As Federal infantry continued forward, the McDowell steamed upriver and shelled Camp Bacon with an eight-inch howitzer, forcing the camp's abandonment and leaving behind food, tents, blankets, equipment, and twelve hundred pairs of shoes. A final Southern stand at the fairgrounds east of town, where the state armory had been moved, also collapsed under howitzer fire and the rapid Union advance, and the retreating force left behind its two unused six-pound cannons. By 11 a.m. Lyon entered Boonville and received the town's surrender from local citizens while Jackson fled toward southwest Missouri to join Price, who was also withdrawing from Lexington. Although casualties were light, with three Southerners killed and five to nine wounded and the Federals losing five killed and seven wounded, the result was highly significant: Lyon had toppled the state government, sent Jackson, the general assembly, and the State Guard southward, denied Price and Jackson time to build an army in the Missouri heartland, and helped secure Missouri for the Union by making the Missouri River a Federal highway that blocked northern recruits from reaching the Southern cause.
