This question can have many answers but ill try to answer it in the north slaves werent profitable so most northerners didnt have slaves and eventually slavery was seen as morally wrong in the north so in the south once abraham lincoln became president the south became its own coutry and the civil war began so after the north won slavery was abolished in the south.
Following the French and Indian War, the victor (Britain) existed as the European power with the strongest colonial rule in North America due to demands made against France and the land taken at the end of the war.
According to Justice Brown's opinion, social equality must be the result of what three factors? He says that if the "two races are to meet upon terms of social equality, it must be the result of natural affinities, a mutual appreciation of each other's merits and a voluntary consent of individuals."