1h 16min | Drama, Music | 6 April 1940 (UK)
Director: Pen Tennyson
Stars: Paul Robeson, Edward Chapman, Simon Lack
http://www.imdb.com/title/tt0031828/
The release date is interesting to me. Part of the story includes the trouble in Europe, and talks about coal needs "if we go to war." Britain & France declared war on Germany 3 Sep 1939 after Poland was invaded 1 Sep (the filming date listed in IMDb); I don't remember seeing that headline in the montage. Then they had an absence of fighting until 10 May 1940, when Germany overran France and Benelux in a few days. That Sep-May period is now called the Phoney War, and this film was released in April. After the opening credits we get a title card of "South Wales 1938", but by the time the threat of war is mentioned, time has passed. Per the Wikipedia article, "Filming was completed in September 1939 but producer Michael Balcon and director Pen Tennyson were forced to recut the ending of the film in the new atmosphere following the outbreak of war." But war hadn't broken out yet, only declared?
So, Note to Self: try to track the timeline better to maybe answer questions above.
We get a spot of racism in the story, nicely quashed by the man who brought Robeson into the Welsh mines (so that his bass can join the choir) with something like "he's as black as any of us down in the pit" plus praise for his friendship.
Robeson is excellent, as always. We get just enough singing to label this Music (they have an amateur men's choir). The real triumph of the film is that Robeson is the hero, in the self-sacrificing sense you get a lot in war films. This isn't war, but a dangerous occupation, and a certain death situation. The Wikipedia page calls How Green is My Valley ('47) a similar film, but I find that one sentimental/maudlin. This film is focused on fewer characters, and illustrates the dangers just as well. And yes, they have an actual song bird in a cage to help them determine the oxygen sufficiency: the canary in the coalmine.
Robeson appears (and sings) only once more on film in '42. It's an anthology film, not a musical, and he's not the star, but I'll add it to the quest anyway.
CAPAD, Ealing Studios (uncredited), dir. Tennyson; 8