An American Tragedy is a 1925 novel by American writer Theodore Dreiser. He began the manuscript in the summer of 1920, but a year later abandoned most of that text. It was based on the notorious murder of Grace Brown in 1906 and the trial of her lover, Chester Gillette. In 1923 Dreiser returned to the project, and with the help of his future wife Helen and two editor-secretaries, Louise Campbell and Sally Kusell, he completed the massive novel in 1925. The book entered the public domain in the United States on January 1, 2021.

Theodore Herman Albert Dreiser was an American novelist and journalist of the naturalist school. His novels often featured main characters who succeeded at their objectives despite a lack of a firm moral code, and literary situations that more closely resemble studies of nature than tales of choice and agency. Dreiser's best known novels include Sister Carrie (1900) and An American Tragedy (1925).