What aspects of the Civil War might have caused this dramatic shift in style, form, and thematic discourse in American literature?

The American Civil War greatly caused a dramatic shift in style, form, and thematic discourse in American literature because it affected the people in a way that they question its morality and reality. The works after the Civil War were mainly focused on how they experienced the war and its effects. It also sparked some antiwar works and some focused more on patriotism.