I just discovered the work of Moise Kisling. I'm delighted to find his pre-beatnik images. He was painting in the teens to the 30's in Paris and hanging out with the Montparnasse crowd. Look how modern his work is. It definely reminds me of '50's beatnik jazz.
Kiki de Montparnasse
I read somewhere that his work falls into a category called "Post Impressionism" but his style reminds me of American WPA artists.