Realism and naturalism emerged in the mid-19th century, reshaping literature with their focus on everyday life and scientific determinism. These movements rejected idealization, instead depicting the harsh realities of industrialization, social inequality, and human nature. Authors like Mark Twain, Henry James, and Edith Wharton used detailed descriptions, vernacular language, and psychological depth to create authentic portrayals of society. Their works exposed social issues, challenged conventional morality, and continue to influence literature and culture today.