Actually Suikoden is closer to chinese mythology than japanese, though it of course has lots of japanese references aswell.

And ninjas, leaves & whatnot is hardly something unique. I don't recall the ninja town having an academy however...

But there's a Hanzo & a Sasuke in it. Based on the true ninjas Hanzo Hattori & Sarutobi Sasuke.

*Include 5 pages of japanese story that nobody but Terra cares about here*