Man from Deep River is always mentioned as the start of this subgenre, but it is not a cannibal movie. It's not even a horror movie. It tells the tell of a white guy who gets lost in the jungles of Thailand and is captured by a local tribe. Eventually, he finds love and purpose there.
This film is more of an outgrowth of the mondo film subgenre. It delights in showing us the shocking aspects of tribal life, most of which involve abusing animals. Jesus, I've never seen a work of fiction with so much real animal torture in it. We're forced to watch crocodiles and snakes chopped up alive, a mongoose forced to fight a cobra, a presumably real monkey getting its skull chopped off, cockfights, and a goat getting its throat gruesomely slit. I'm no member of PETA and I've got no problem with hunting, but this nothing I want to see to create a fictional story.
There is one small cannibal scene in the film, which presumably was the seed that inspired the rest of the Italian cannibal film explosion. A small group from the neighboring tribe discover a couple in the woods. They kill the man, then proceed to rape and eat the woman. It's disturbing, but it's really only a small section of a film that is mostly about the protagonist mooning over his native wife. It must have been enough, though, to stick in peoples' minds so that they wanted more.
Watched: DVD from Shriek Show.
The Walking Dead 3.07: "When the Dead Come Knocking" (2012) directed by Daniel Sackheim
Mostly setup for the mid-season finale that's coming next. Merle and the Governor torture, sort of, Glenn and Maggie to get them to reveal where Rick and company are hiding. It's TV show torture and nothing compared to what the comic character would've done in the same situation (how cute and meta that the Governor threatens to cut off Glenn's hand!). I suppose they wouldn't want to alienate the audience, though, what with the highest ratings of any cable show and all.
Later, Rick brings most of the group to the edge of Woodbury on a rescue mission while, at the same time the Governor sends a small group to scout out the prison. Hopefully the dual front battle in the next episode is worth the build up.