The movie begins with "Once upon a time?" That automatically frees it from any historical nit-pickers. Really? You mean to say that a group of vengeful Jews, headed by a Southern goy with an attitude & accent that's a mix of Marlon Brando & Jon Voigt ("Those Nat-zees need to be dee-stroyed.") and so they do, without conscience, then plot to trap a passle of head Nazis from Hitler on down and annihilate them in one felled swoop - and thereby end the war?
Col. Landa, a slimy Nazi officer who amorally & unemotionally searches out & annihilates Jews on his own, becomes a foil to our leader of the Inglorious Basterds (far as I know, Tarantino never has explained the misspellings), and it's a tense uphill climb to one climactic moment after another with a few other characters introduced along the way to spice up the tension - a Jewish survivor of one of Landa's raids who plans revenge of her own making, a Nazi hero who takes more than casual interest in her, Landa's constant showing up like a bad pfennig, etc.
They have appropriate nicknames: Landa is the Jew Hunter; one of the more vicious Basterds is the Bear Jew who beats Nazis to a pulp with a baseball bat (before they are summarily scalped "Apache style;" the Nazi war hero is the "German Sgt. York."
Cinematic references are dropped with relish throughout the film. Tarantino savors names & titles, especially: Leni Reiffenstahl, Emil Jannings, Pierre Fresnay - even the name of the Basterd leader - Aldo Raine (Aldo Ray); one can almost hear Tarantino chortling over his esoteric jokes.
The film is divided into parts: Chapter 1, at a French farmhouse where Landa introduces his cat/mouse mannerism - his playful charm into sudden carnage; Chapter 2, the formation of the Basterds; Chapter 3, introducing the Jewish girl disguised as a French cinema operator in Paris, etc.
Throughout the film, one is (as always with T's movies) impressed by his understanding and use of cinematic techniques. Dramatic lighting (sometimes with available light, others with special lighting set-ups), expressive use of close-ups (on people & objects), editing (I understand he fought constantly with his favorite editor Sally Menke over his penchant for stretching scenes; for her it made them drag, for him it created just the right kind of sadistic tension that characterizes his style. The lengthy monologues remain, pushing the film to its 2 1/2 hour length. That, along with his emphasis on irony, cynicism, pain, mutilation & sado-masochistic maiming, are also more than evident here.)
T's ability to develop clever dialog mixed with improvisation is a key factor in the creation of his characters; and, as in earlier films, it becomes another strong element of his style.
T's control over his cast is equally admirable. Christoph Waltz (Col. Landa), Melanie Laurent (the Jewish owner of the Parisian cinema house), and - especially - Brad Pitt (Aldo Raine) are unrelenting in the wide stretches called for in their roles.
In fact, it is the writer//director's cinematic talent that comes through with strength in each scene. Unfortunately, at least for me, the parts do not add up to a satisfying whole. Strong & powerful moment by moment as the movie is, the final result is a flat, empty feeling of artistry over substance. The concluding postscript suggests that revenge is, indeed, sweet - and a movie doesn't really need all that time to prove it.