Andrew Johnson was the 17th President of the United States, taking over after Abraham Lincoln's assassination. He handled reconstruction poorly and was the first president to be Impeached, but was acquitted for some reason.
Johnson didn’t believe that black people should be slaves and oversaw the passing of the 13th Amendment to the Constitution that abolished slavery permanently. During the American Civil War also he had worked to help end slavery with Lincoln. Despite this Johnson believed that black people were inferior to whites and institutionalized discrimination against black Americans including denying them the vote.  Incidentally Johnson himself was unfit to govern and as mentioned above narrowly escaped impeachment.