Die grünen Teufel

While I like this movie for all the wrong reasons, it doesn't come close to doing justice to the Robin Moore book on which it was very loosely based. It's pretty obvious that much of it was filmed stateside, but in that it was one of the few - if not the only - Vietnam War movies made in the 60's it's historically significant. I also know that The Duke visited several US Army SF camps in SE Asia in preparation for this film - as well as to show his support for our service men.

If you're interested in the subject matter, however, READ THE BOOK! It's very gritty and much of it is from a unique first-person perspective.