I've heard that the actual storyline of Star Wars (and events of Episodes V and VI as well) was based in part on the 1958 film The Hidden Fortress (actually there's already a lot of good info in that node), directed by (super-cool) Japanese film-director Akira Kurosawa. To see if this was true, I borrowed a copy from somebody. Despite the horrendous translation, I'd have to agree that there are a lot of similarities, although there are enough differences that it might just be coincidence. I'll let you judge.

Here's the similarities: A nation is in turmoil. Two companions, mostly there for comedic relief, are rounded up and work as slaves (I'm thinking R2-D2 and C-3PO captured by the Jawas) to search for gold, until a rebellion occurs during which they manage to escape. They are then trailed by a mysterious stranger (the super-cool Toshiro Mifune), who eventually joins them (his character appears to be a combination of Obi Wan Kenobi and Luke Skywalker). They successfully make it to a Hidden Fortress in the mountains (some might call it a Rebel Base). A princess must flee from her homeland to a nearby region and seek protection, and must use her country's hidden gold to rebuild her nation. To do this, she must transport herself and the gold to a neighboring region sympathetic to the princess. The mysterious stranger is actually the general of her nation's (no longer existant) army, who agrees to use the two strangers and his own skills to transport her and the gold (the two companions now take the part of Han Solo and Chewbacca, given their shadier antics and the well-deserved distrust extended to them by the princess and general). Regardless, the four of them team up and try to make it to above-mentioned neighboring nation, sneaking through various blockades and getting into various sword fights, all the while pursued by the opposition's general (who I think corresponds nicely to Darth Vader).

Unfortunately, folks, the translation I watched was so terrible, not even the names were right (it was apparantly translated from Japanese to Chinese to English, and a lot was lost, including the actual names of the characters -- names were translated to Shee, Yau, Ting, Tin, etc.). I looked up names for research, but they are all Japanese so I can't really tell you who's who.

Fans of Star Wars should probably try to find this, though. The translation is horrible (as said, but needs repeated), but it's still a good flick nonetheless.