As an aside, I am usually not the guy who enjoys watching foreign movies, especially those where I have to read "subtext" at the bottom of the screen since the movie hasn't been dubbed in English, and spoken in the original language.
If you want to learn more about Japanese culture, check out the movie "RAN" I am not a movie buff, but I know that this movie was directed by one of the most famouse (recent) directors of Japan (though he is dead now and I don't know his name.)
"Ran" is basically the retelling of Shakespeare's King Lear, but told through a Japanese samurai family, rather than an English one. Japanese adventure movies are bloody, bloody, gory. When a katana wielding samurai splays open an opponent, blood sprays all over the attacker and the wall behind him, and running all over the floor like a spilled 55 gallon barrel of blood - seriously.
There's a scene of a Japanese castle sitting in a valley, with thousands of flintlock bearing ashigaru (samurai henchmen) on a hill, which you can't see clearly due to volumes of black powder smoke filling the air, except for the flashes of gun fire, onto the castle that is splintering from bullet hits, dead Japanese defenders and rivers of blood flowing out - all the while some classical European musical score for sound - its an awe inspiring scene.
The final battle scene involves three armies each distinctly wearing the colors of their noble house (so you can easily tell who is fighting for whom) with thousands of blades and guns blazing, awesome filiming I tell you!
Like I said, I'm not into subtext movies, but this has got to be one of the best foreign films I have ever seen - and I haven't watched it in almost 20 years. If you want to get the feel for Japanese medieval war - watch this movie (don't know where you can find it, but do it. You won't regret it.)
GP