“I knew at the beginning that I was not doing science fiction. I was doing a space opera, a fantasy film, a mythological piece, a fairy tale. I really thought I needed to establish from the start that this was a completely made up world so that I could do anything I wanted.”
-George Lucas from Star Wars the annotated screenplays by Laurent Bouzereau
Yes, there is the answer in the first line - “A Space Opera”. That has been my point from the beginning. Lucas, like so many, has this false image that science fiction has to be real. Yet he correctly labels Star Wars as a space opera - one of the subgenre’s of science fiction where everything he wanted to do was normal. And he only seems to use the word fantasy in terms of things aren’t based on solid science rather than the Tolkienesque type of fantasy. Making up worlds is the first step to creating any space opera universe.