As an enslaver and a Democrat, President Andrew Johnson was

Andrew Johnson was a Democrat who had enslaved people, and his approach to Reconstruction clashed with the plans of many Republicans in Congress. Their disagreements led to repeated political conflicts, so the correct choice is “often at odds with Republicans in Congress.” Johnson was not involved in negotiating the end of the Civil War, and he was not assassinated; he succeeded Abraham Lincoln after Lincoln’s assassination.

AI-written and checked against the verified answer.