This episode, and much of the series, is filmed at George Lucas' "Skywalker Ranch". Lucas made the ranch available for the interviews as a gesture of gratitude. He based much of the structure of the Star Wars series on Campbell's description of the Hero cycle in his book "The Hero With a Thousand Faces" and he credits Campbell with the incredible success of the films.
Campbell: When you see the earth from the moon, you don't see any divisions there of nations or states. This might be the symbol, really, for the new mythology to come. That is the country that we are going to be celebrating. And those are the people that we are one with.