James J. Corbett, also known as "Gentleman Jim," was an American professional boxer born on September 7, 1866. He is best known for being the first heavyweight champion of the world under the Marquess of Queensberry rules, which introduced gloves and a more structured format to boxing. Corbett's boxing style emphasized speed and technique, making him a pioneer in the sport. Corbett's most famous fight took place in 1892 against John L. Sullivan, where he won the heavyweight title. After retiring from boxing, he pursued a career in acting and appeared in several films, further solidifying his legacy in American sports and entertainment history.