Been some time since I've watched 1974's The Yakuza starring Robert Mitchum and the great Takakura Ken (Black Rain in hollywood with Michael Douglas, countless Japanese movies). rewatched it last night.

Not quite Martial Arts film, but it had some scenes with sword/katana fights as well as discussing the Japanese culture, especially the Yakuza (gangsters) and giri (obligation, favor that can't be repaid, burden)

What a great underrated film. Can't reco this highly enough for anyone interested.