AH, Glad to see Taiwan come up!
I'm pretty sure I linked to this film 3 years ago (
in this thread), but I think it was simply overlooked.
It's a good movie, and from the standpoint of authentic costume, architecture, and weaponry --- VERY VERY GOOD. All the laraw there look correct, and the Japanese troops look authentic of the time period. In the beginning there's even very period-correct Han weaponry.
I believe the suicidal tendencies you mention has more to do with the inevitability of defeat rather than a cultural norm. Keep in mind that Taiwan has been invaded by the Dutch, Koxinga, Qing Dynasty, French, Americans, Japanese and the Chinese Nationalist Party (Kuomingtang). Each invader has been met with fierce resistance, but aside from some smaller-scale fights, the islanders, no matter their ethnicity, has almost always been forced to fight much more powerful forces backed by economically, politically, technologically and numerically superior countries. Not to mention, this was the "wild wild East"... on top of all these invasions, settlers fought natives, different tribal groups launch raids against one another and the settlers, and the Fujianese and Hakka descendants on Taiwan fought with one another often. During the Qing Dynasty, there were rebellions and uprisings every few years. The Fujianese and Hakka settlers, the Plains tribes, the Bunun, the Paiwan, the Rukai... they all underwent similar struggles, no matter how small scale... the Seediq story at Wushe, however, has become an epic and kinda well-known part of Taiwanese history.
This is a good website for more history about the stuff that happened in Wushe
(which is what Seediq Bale or Warriors of the Rainbow Bridge is about)
http://www.takaoclub.com/monaludao/wusheincident.htm