Final answer:
Mark Twain borrowed characteristics from his observations of society, humor, and pre-Civil War America to create authentic and satirical characters in his works, such as those in Adventures of Huckleberry Finn and The Gilded Age.
Step-by-step explanation:
Mark Twain, a central figure in American Literary Realism, often infused his characters with characteristics he borrowed from a diverse range of influences. These influences could include aspects of regional humor, satire, and his own experiences in a pre-Civil War America where slavery was still prevalent. Characters like the ones found in his novel Adventures of Huckleberry Finn reflect Twain's critical perspective on social issues and his knack for nuanced, vibrant storytelling.
Twain gave his characters a sense of authenticity by drawing from the society and environments around him. In The Gilded Age: A Tale of Today, co-authored with Charles Dudley Warner, Twain uses satire to critique the corruption of the era, and by doing so, creates characters who personify the greed and folly he observed in late 19th-century America.