Gilbert M. "Broncho Billy" Anderson (born Maxwell Henry Aronson; March 21, 1880 – January 20, 1971) was an American actor, writer, film director, and film producer, who was the first star of the Western film genre. He was a founder and star for Essanay studios. In 1958, he received a special Academy Award for being a pioneer of the film industry.

Anderson was born Maxwell Henry Aronson in Little Rock, Arkansas, the sixth child of Henry and Esther (Ash) Aronson, both natives of New York. His younger sister was actress and singer Leona Anderson. His family was Jewish, his father's parents having emigrated to the United States from Prussia, and his mother's from the Russian Empire. His family moved to Pine Bluff, Arkansas when he was three years old. He lived in Pine Bluff until he was 8, when he moved with his family to St. Louis, Missouri. When he was 18, he moved to New York City and appeared in vaudeville and the theater, supplementing his income as a photographer's model and newspaper vendor. In 1903, he met Edwin S. Porter, who hired him as an actor and occasional script collaborator.

Anderson played the dancing tenderfoot and the train passenger who gets shot and bandit #1 in The Great Train Robbery (1903). Seeing the film for the first time at a vaudeville theater and being overwhelmed by the audience's reaction, he decided to work in the film industry exclusively. He began to write, direct, and act in his own Westerns under the name Gilbert M. Anderson.

In 1907 in Chicago, Anderson and George Kirke Spoor founded Essanay Studios ("S and A" for Spoor and Anderson), one of the major early movie studios. In 1909, he directed the film with the first known instance of the pie-the-face gag, Mr. Flip. Anderson acted in over 300 short films. He played a wide variety of characters, but he gained enormous popularity from a series of 148 silent Western shorts and was the first film cowboy star, "Broncho Billy." Many of these were shot in Niles, a small town in Alameda County, California, south-east of San Francisco, where the nearby Western Pacific Railroad route through Niles Canyon proved to be a very suitable location for the filming of Westerns.

Writing, acting, and directing most of these movies, Anderson also found time to direct a series of "Alkali Ike" comedy Westerns starring Augustus Carney. In 1916, Anderson sold his ownership in Essanay and retired from acting. He returned to New York City, bought the Longacre Theatre and produced plays, but without permanent success. He then made a brief comeback as a producer with a series of shorts with Stan Laurel, including his first work with Oliver Hardy in A Lucky Dog (filmed in 1919, released in 1921). After a series of failures as a Broadway producer, he retired again after 1920, this time permanently.

Anderson sued Paramount Pictures for naming a character "Bronco Billy" in Star Spangled Rhythm (1943) and for depicting the character as a "washed-up and broken-down actor," which he felt reflected badly on him. He asked for $900,000, but the outcome of the suit is unknown.

In 1958, Anderson received an Honorary Academy Award as a "motion picture pioneer" for his "contributions to the development of motion pictures as entertainment."

At age 85, Anderson came out of retirement for a cameo role in The Bounty Killer (1965).