Check out section 3 of the Fourteenth Amendment.
Instead of hundreds of messy treason trials, congress essentially banned all confederate senior officers and politicians from ever holding a US or state office.
So, without bloodshed, the 14A kept the troublemakers from ever stirring things up again.
That is an interesting comment.
I thought most of them, with the possible exception of General Lee, had their citizenship and rights restored.
Didn't some of the Confederates go on to serve President Grant, and be elected to Congress, serve as governors, and be appointed to federal judgeships, and to serve as Generals in the U.S. army?
Read the last sentence of section 3 of the XIV Amendment.
“But Congress may, by a vote of two thirds
of each House, remove such disability.”
That’s nonsense. You would have known better if you’d ever learned of President Andrew Johnson’s December 25, 1868 “Proclamation 179Granting Full Pardon and Amnesty for the Offense of Treason Against the United States During the Late Civil War”
http://www.presidency.ucsb.edu/ws/?pid=72360