Night on Bald Mountain was one of the musical pieces featured in Disney's 1940's film Fantasia.

The answer is true because "Night on Bald Mountain" is indeed one of the musical pieces featured in Disney's 1940 film, Fantasia. The film consists of a collection of animated segments set to classical music, and "Night on Bald Mountain" is prominently featured as the final segment. Composed by Modest Mussorgsky, it portrays a dark, intense, and supernatural scene, showcasing the powerful music and the vibrant animation techniques used in the film.