Although Yoda’s design as Star Wars’ little green alien is iconic now, the Jedi Master was originally going to be played by a monkey. Introduced in Star Wars: The Empire Strikes Back, Yoda continued Luke Skywalker’s training in the ways of the Force. Yoda’s combination of wise teachings and goofy antics quickly made him a fan-favorite character. Due to this, Yoda has made major appearances in a variety of Star Wars media since The Empire Strikes Back, including the prequel trilogy, Star Wars: The Last Jedi, and animated shows like Star Wars: The Clone Wars and Star Wars Rebels.
Throughout all of these renditions, Yoda’s design has changed multiple times. For the original Star Wars trilogy, George Lucas enlisted Jim Henson, the creator of the Muppets, to help design a puppet for Yoda. When making the Star Wars prequels, Yoda’s designers realized that Yoda would be younger than he was in The Empire Strikes Back, so they updated his puppet for The Phantom Menace. To make it possible for Yoda to engage in lightsaber duels in Attack of the Clones and Revenge of the Sith, the team switched Yoda to a CGI character. Many viewers did not like this change though, so Yoda returned as a puppet in Star Wars: The Last Jedi.
However, Yoda’s original design did not involve a puppet or CGI. According to one article (via Culture Slate), Lucas initially considered having Yoda be portrayed by a monkey wearing a mask and carrying a cane. J.W. Rinzler’s 2010 book, The Making of Star Wars: The Empire Strikes Back, revealed this behind-the-scenes information and even included pictures of monkey Yoda with his trainer. Ultimately, Lucas decided not to use the monkey due to both work and character limitations.
Why George Lucas Decided Not to Cast A Monkey As Yoda
The first major reason Lucas decided against using a monkey to play Yoda was simply that the monkey was difficult to work with. Even with a trainer, it was hard to direct the monkey to perform specific actions. One Star Wars: Empire Strikes Back crewmember, who had worked on the primate scenes in 2001: A Space Odyssey, was even able to warn Lucas about the potential problems of working with monkeys. Rinzler’s novel included a quote from the crewmember, saying “Look, the monkey's just going to pull the mask off over and over again. It's never going to work.” In contrast, Yoda’s puppeteer and voice actor, Frank Oz from the Muppets and Sesame Street, had complete control over Yoda and could make him perform specific tasks.
Additionally, although the monkey was an appropriate size to portray Yoda, it did not work well as a fully developed character. The images in The Making of Star Wars: The Empire Strikes Back were only screen tests, but they still revealed that the monkey’s Yoda mask was not believable as a real alien. Since the mask could not change shape, it also made it impossible for Yoda to show any facial expressions or move his mouth for speech. After these screen tests, Lucas learned that a puppet was far more practical and expressive for playing Yoda than a monkey, resulting in the classic look that Star Wars fans know today.