Just a quick response. I can't give any hard numbers, but there were large groups of people throughout Arkansas and Missouri who moved to avoid Confederate Guerrillas, Federal Jay-hawkers and outlaws, particularly along the border with Kansas and Oklahoma and along the Missouri River Valley area known as "Little Dixie". Depending on where their loyalties lied, loyal Missourians and Arkansans moved to Iowa, Illinois or other parts of Missouri that were better controlled by the army. For Secessionist Missourians and Arkansans, they moved further south into Arkansas and down to Texas.