Fires on the Plain
(1959)

A powerful anti-war film where soldiers resort to cannibalism.

The Japanese Army in the Philippines at the end of WWII is without hope. A starving and sick soldier named Tamura comes across two other Japanese soldiers (Nagamatsu and Yasuda) who claim to have survived on "monkey meat".

Nagamatsu finally kills Yasuda and while butchering him, Tamura is so repulsed that he kills Nagamatsu.  Tamura then heads for the fires on the plains to find someone normal where he is killed by sniper fire.  

Thanks Don P!