This is a hell of a good film. It's really funny and also really gritty. The Wild bunch and Bonnie and Clyde get a lot of the credit for upping screen violence, but The Dirty Dozen features our heroes locking all the Nazis in a shelter (With their wives and numerous innocents), and pouring gasoline and grenades in the vents. It's pretty intense, and undoubtedly exciting.
Actually, IIRC, servants were the only innocents and they were told to leave.