In an effort to curb guerilla warfare in Missouri and Kansas, Union General Thomas Ewing who commanded at Kansas City, on Tuesday, August 25, 1863 issued General Order No. 11. All persons in Jackson, Cass, and Bates counties, Missouri, plus parts of Vernon County, were immediately to evacuate their homes.
Those who could prove their loyalty to the Union would be permitted to resettle at military posts. All others had to leave the area. Eventually, an estimated twenty thousand people around the Kansas City area were displaced, with their abandoned homes, barns, and crops often destroyed.
While having little or no direct effect on partisan fighters like the Redlegs or border ruffians such as Quantrill, the order caused deep animosities against the Union which would last for years.