I've watched Kagemusha, and recently finished the Hagakure, 47 Ronin (not really Sengoku-era, but an essential piece of Japanese literature) and am reading a great book now called 'The Nobility of Failure' by Ivan Morris.
"It is because people's minds are not logical and enlightened that the Empire is in disorder. If the country is not properly ruled there will be no end to rebellions. And if anyone wishes to get the knowledge of how to rule it properly he will only find it in books. That is why the publication of books is the beginning of beneficient rule."