We can be sure that all persons of mixedAfrican and American ancestry were classified as colored persons (or as 'negroes') prior to the Civil War.
(We; can be; sure that all persons of mixedAfrican and American ancestry were classified as colored persons (or as 'negroes') prior to the Civil War) (all persons of mixedAfrican and American ancestry; were classified; as colored persons)
We all persons of mixedAfrican and American ancestry
can be were classified
sure that all persons of mixedAfrican and American ancestry were classified as colored persons (or as 'negroes') prior to the Civil War
as colored persons