A lot of the musicians in this series were only filmed late in their lives because in their younger days, during the 1930s or earlier, nobody in Hollywood was paying much attention to what was going on in juke joints in poor African-American areas in the deep South. There's little enough of, say, Robert Johnson's work available on audio as it is, but to actually be able to see the man perform is something we can only imagine.
You might think that the great Bessie Smith, the most popular and perhaps the most influential Depression-era blues singer, would have fared better, but sadly, no.
Smith was one of the top-selling singers in the 1920s before the economic crisis at the end of the decade flattened the recording industry, and also found her vaudeville career wiped out by the invention of sound in motion pictures. She only made one foray into the movies herself, in a 1929 short film called St. Louis Blues, which is basically an archaic version of a music video, with a minimal plot centering on Smith as a woman who's been abandoned by her caddish boyfriend and loses herself in alcohol and song. It's her only known appearance on film, but it's certainly a powerful one, and rightly preserved in the National Film Registry at the Library of Congress. The clip below is just a portion of the full 16-minute film, but it's all I could find online.
Smith's film legacy might have fared better if she'd lived longer, as happened with her contemporary Louis Armstrong, who broke into Hollywood in the mid-1930s. But instead she died tragically in 1937, the victim of both a car accident and the subsequent refusal by the nearest hospital, a whites-only establishment, to treat her injuries.
Since I've only got the one clip for Bessie, I'll supplement that with a couple of tangential extras: Two songs by the recently deceased Bo Diddley. Arguably, Diddley was enough of a bluesman that he could get his own entry in this series, but a) I'd argue that he's really too close to the line between rock and blues, and in many ways is the line between rock and blues, and b) I can only find video clips of him playing rock songs anyway. Without further ado: Here's "Road Runner," from 1960:
And here he is again, apparently sometime in the 1970s.