John Newton Sarber and Sarber County, Arkansas

The book John Newton Sarber and Sarber County, Arkansas is not revisionist history, but a re-visiting of original documents and sources during the time of Reconstruction in Arkansas. The book traces the life of John Sarber, a Radical Republican in Arkansas politics, from his boyhood in Lawrenceville, Pennsylvania, to his abolitionist family's move to Kansas, his fighting with the 2nd Kansas Cavalry, and his becoming active in Arkansas, and the contributions he made in the State Legislature.. He also served as a contorversial U. S. Marshal in Fort Smith, Arkansas. Was he or was he not a "carpetbagger?"
Why was a county in Arkansas named for him?