Union Brigadier General Nathaniel Lyon took over the Jefferson City, Missouri on June 15th 1861, the state capitol. Two days later Lyon fought with some of the Confederate Missouri State Guard near Boonville, Missouri. A part of the Confederate State Guard along with the pro–secession Missouri Governor Claiborne Fox Jackson fled southwest toward Benton County with the Union troops behind them.
Most residents of Benton County, Missouri were of Confederate sympathies, but the German immigrants in the area were pro-Union. They formed the Benton County Home Guard in early June 1861 under the command of Captain Able H W Cook at Cole Camp. At the same time in nearby Warsaw, Missouri Confederate leaning Captain Walter S O’Kane and Captain Thomas W Murray organized the Warsaw “Grays” and “Blues”.
On June 18th 1861 O’Kane’s men left Warsaw and marched toward Cole Camp. A local citizen John Tyree reported the movement to officers at Cole Camp. After making this report he was captured by some of the Confederates, tied to a tree and shot. Despite the warning the men of the Benton Home Guard were caught sleeping in the early morning hours of June 19th 1861. O’Kane’s men hit a portion of the Home Guard to the east of Heisterberg barn, firing a volley into the men. A company of Home Guard to the north of the barn; under Captain Elsinger fired into O’Kane’s flank, but quickly ran out of ammunition and were forced to withdraw.
The Union had 34 men killed, 60 wounded and 25 men taken prisoner. The Confederates lost 7 killed and 25 wounded. More importantly O’Kanes men captured 362 muskets that would be used at the Battle of Wilson’s Creek.