The man was neither legally hung nor hanged, he was lynched.
We are not told the nature of his alleged crime, or the evidence against him, but it has been noted elsewhere that lynchings before the Civil War were almost entirely of white people and were not restricted to any region of the country.
After the Civil War 2/3 of US lynchings were in Southern states and 2/3 of the victims were African-Americans, nearly all men, but including some women.
The 1866 Memphis white riots killed 46 blacks and injured 75, with 100 more robbed and 5 black women raped.
The 1921 Tulsa white riots killed up to 300 black men, women & children.
None of that was in evidence before the Civil War.