The states of Delaware, Maryland, West Virginia, Kentucky, and Missouri had been border states during the Civil War (i.e. slave states that remained in the Union), while Oklahoma was not then a state and had been settled primarily by Southerners and by Native Americans under federal removal policy. Prior to the "Brown v. Board" decision, all required segregation in their public school systems. Nonetheless, none of the 12 U.S. Senators or 39 U.S. House Representatives from these states signed the Manifesto.