David Belasco (July 25, 1853 – May 14, 1931) was an American theatrical producer, impresario, director, and playwright. He was the first writer to adapt the short story Madame Butterfly for the stage. He launched the theatrical career of many actors, including James O'Neill, Mary Pickford, Lenore Ulric, and Barbara Stanwyck. Belasco pioneered many innovative new forms of stage lighting and special effects in order to create realism and naturalism.

David Belasco was born in 1853 in San Francisco, California, the son of Abraham H. Belasco (1830–1911) and Reyna Belasco (née Nunes, 1830–1899), Sephardic Jews who had immigrated to the United States from London's Spanish and Portuguese Jewish community during the California gold rush. He began working as a youth in a San Francisco theater doing a variety of routine jobs, such as call boy, script copier, or as an extra in small parts. He received his first experience as a stage manager while on the road. He said, "We used to play in any place we could hire or get into—a hall, a big dining room, an empty barn; any place that would take us."

From late 1873 to early 1874, he worked as an actor, director, and secretary at Piper's Opera House in Virginia City, Nevada, where he found "more reckless women and desperadoes to the square foot…than anywhere else in the world". His developmental years as a supporting player in Virginia City colored his thoughts and eventually helped him to conceive realistic stage settings. He said that while working there, seeing "people die under such peculiar circumstances" made him

"all the more particular in regard to the psychology of dying on the stage. I think I was one of the first to bring naturalness to bear in death scenes, and my varied Virginia City experiences did much to help me toward this. Later I was to go deeper into such studies."

His recollections of that time were published in Hearst's Magazine in 1914.

By March 1874, he was back at work in San Francisco, eventually managing Thomas Maguire's Baldwin Theater. When Maguire lost the theater in 1882, Belasco relocated to the East Coast, bringing his practical western experiences with him. The West allowed him to develop his talents as not only a performer, but in progressive production design and execution.

A gifted playwright, Belasco went to New York City in 1882. He worked as stage manager for the Madison Square Theatre (starting with Young Mrs. Winthrop), and then the old Lyceum Theatre, while also writing original plays. By 1895, he was so successful that he was considered America's most distinguished playwright and producer.

During his long creative career, stretching between 1884 and 1930, Belasco either wrote, directed, or produced more than 100 Broadway plays, including Hearts of Oak, The Heart of Maryland, and Du Barry, making him the most powerful personality on the New York City theater scene. He also helped establish careers for dozens of notable stage performers, many of whom went on to work in films.