1. The Empire Strikes Back is the Star Wars film with the saga’s lowest body count, with just 30 deaths appearing on screen.
2. Originally George Lucas envisioned a trip to Darth Vader's home during Empire. We would've seen that he resided in a big Gothic castle, surrounded by lava, and full of living gargoyles which Vader kept as pets.
3. Another early plan for the movie was that Yoda would be played by a trained monkey who would be wearing a mask and carrying a cane.
THE EMPIRE STRIKES BACK: (No joke) The Empire team initially hired a trainer and a MONKEY to hold a cane & play YODA. pic.twitter.com/tQPt5Jebqp
— will mccrabb (@mccrabb_will) November 18, 2013
4. Sticking with Yoda, after being switched from primate to puppet his look was based on Albert Einstein, particularly his "wise eyes". Bonus pub quiz fact - The name Yoda was chosen because it is the Sanskrit word for 'warrior', although most hardcore fans will tell you he originally went by the name of 'Minch' (which is in fact still officially his first name - Minch Yoda).
5. Originally, in Leigh Brackett's first draft of the script, Darth Vader was not Luke's father. Luke actually met his real dad - still called Anakin - who claims that he sent away Luke and his secret sister for their own safety (not Leia at this time, an unidentified 'sister' who was well on the way to becoming a Jedi too). Before Luke leaves his father to head off to face Vader, Anakin Skywalker administers the oath of a Jedi Knight. During this ritual Obi Wan Kenobi, Anakin, Luke and Minch (Yoda) cross their lightsabers, Luke then swears an oath to "dedicate my life to the cause of freedom and justice."
6. Keep your eyes peeled during the asteroid sequence in The Empire Strikes Back, because one of the asteroids is actually a shoe and another one is a potato.
7. Remember when one of the Alliance Officers tells Han he'll likely freeze to death if he goes out into the cold to look for Luke? Han famously replies "Then I'll see you in Hell". The man he was talking to was Major Bren Derlin, played by John Ratzenberger, better known for his time on Cheers and for providing numerous Pixar voices.
8. Another early script involved Han Solo's stepfather, Ovan Marekal. He was described as a huge political bigwig who had carefully aligned himself with Darth Vader to protect his people. Han had long been estranged from his stepfather, but the Rebels persuaded him to visit 'home' in the hope that he could convince his stepfather to fight against Vader. Things wouldn't have gone Han's way, let's just say that some of that story would find its way into the character of Lando in the final film.
9. The whole Darth Vader/Luke's father reveal came into the story quite late, but after George Lucas settled upon the idea he became overly worried that the big twist would be leaked from the set. In the script, and during the filming, Vader (David Prowse) actually says "No, Obi-Wan killed your father". Just before the film was released one of the final adjustments was the overdubbing of James Earl Jones' voice saying "No, I am your father". Mark Hamill was the only actor to know the truth in advance.
10. When the movie was released on May 21st 1980, The Empire Strikes Back became the first Star Wars film to have a number by its title in the opening credits - Episode V. Back in 1977 the original Star Wars was not called A New Hope nor did it feature 'Episode IV', this came later when Star Wars was re-released as a double bill with Empire on April 10th 1981.
Want more Star Wars trivia?
10 things you might not know about The Phantom Menace
10 things you might not know about Attack Of The Clones
10 things you might not know about Revenge of the Sith
10 things you might not know about A New Hope
10 things you might not know about The Empire Strikes Back
10 things you might not know about Return Of The Jedi
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