Which animated movie was first to feature a celebrity as a voice actor?

The answer is Aladdin because it was the first animated movie to feature a well-known celebrity as a voice actor. Prior to Aladdin, voice actors in animated movies were often not celebrities and their names were not widely recognized. However, Aladdin's filmmakers decided to cast comedian and actor Robin Williams as the voice of the Genie, marking the first time a major celebrity brought their star power to an animated film. Williams' performance as the Genie not only became iconic, but also helped pave the way for future animated movies to cast famous actors and elevate the popularity and appeal of the genre.