And for other things too -- its opening recap crawls were of the type that inspired the ones in Star Wars (though I doubt it was the only serial to do that "receding" crawl).
Lucas usually credits the Flash Gordon
serials as inspiring that -- although after watching clips on YouTube, it appears that only the final Flash Gordon Conquers the Universe
serial with Buster Crabbe (1940) used that style of title crawl. His serial from the previous year -- Buck Rogers
(1939) -- used the Star Wars
crawl, though. I'm not sure if it occurred earlier than that.