A very fun example of this theme is in the franco-belgian fantasy comic series Thorgal, which is set in a Conan-esque fantasy world with all the expected trappings, but in which the gods are highly advanced alien entities and magic is often framed as manipulating extremely complex and powerful heirloom technologies that the living have no frame of reference for as anything other than magic.
The titular outsider hero falls from the stars in a little space pod as a baby and is raised by the local Viking-proxy culture ala Superman or Goku. Quite an engaging read if you're into this blend of sword and sorcery with background sci-fi elements.