In the 1950s (in Japan at least), Tadashi Imai was the most honored Japanese film director, winning the coveted annual Kinema Junpo "Best Film" critics award five times. (As far as I know, only the legendary Yasujiro Ozu won it six times; Kurosawa won it only three times.) A Marxist, Imai made socially-conscious films with a strongly humanistic point-of-view, but in no way were his movies (or at least the ones I've seen) "propaganda." In fact, for me, he most strongly resembles the widely beloved Keisuke Kinoshita, with many of the same strengths and faults as that gentleman. Among his virtues are a very strong feeling for story and character and narrative drive, as well as solid pictorial craftsmanship (though this last admittedly is almost a given among Japanese film artists of the period). Among his shortcomings, like Kinoshita, are a tendency towards unrestrained sentimentality, and a related tendency to hammer moral points home.
Yet, American Japanese film scholars such as Donald Richie and Audie Bock denigrated him (though Richie did admire his 1958 period classic, Night Drum), and even in Japan he is nearly forgotten now. Yet the literary adaptation An Inlet of Muddy Water (1953), the muckraking Darkness at Noon (1956), Night Drum and this film are all first-rate, and highly recommended.
The tragic poignancy of this war film is that the main "warriors" are all schoolgirls and their teachers, requisitioned by the Japanese State to serve as nurses on the front lines with almost no training. Imai spares us no gruesome detail, including wartime operations (with almost no medical equipment or anesthetic), the constant and often futile search for food and water, children killed in bombings or trapped in avalanches, and the futile courage and self-sacrifice of the girls and most of their elders. Most importantly, this movie has the lovely young Kyoko Kagawa (who's still alive and working today at age 85!) as the leader of the girls. She has an outstanding scene near the end in which she performs a traditional dance on the night before a major battle, which the girls know that most of them will not survive. This antiwar classic is essential! (A version with subtitles is on YouTube under "Himeyuri.")