The Wikipedia article on the Wilmington coup of 1898 has this:
In 1868, North Carolina ratified the 14th Amendment, resulting in the recognition of Reconstruction, and in the state legislature and governorship falling under Republican rule. Democrats greatly resented this "radical" change, which they deemed as being brought about by blacks, Unionist carpetbaggers, and race traitors. Freedmen were eager to vote, tending to support the Republican Party that had emancipated them and given them citizenship and suffrage.
For a temporary period[when?] Confederate veterans were barred from office and voting. Many white Democrats had been embittered since the Confederacy's defeat. Insurgent veterans joined the Ku Klux Klan (KKK), which orchestrated considerable violence at elections in order to suppress the black vote.
When and how were Confederate veterans barred from office and voting in NC after the Civil war?