A clearer question: Did the actual people in the party change their views to the opposite or did the title of "Democrat" and "Republican" just quite literally swap?
So for example Republicans pretty much ruled the North while Democrats, the south. Just as Democrats fought to keep slavery while Republicans sought to abolish it.
Did the people stay the same, with the same politics/beliefs and just swapped the name of their party;
or did they keep their name but totally swap beliefs?
Or maybe it isn't quite the simple? I'd love for an explanation on this!