A planet (large continents, mostly steppes, deserts and plains) is settled by nomadic tribes (think Mongols, Tuareg or Apache). The tribes lack written history, but the legends speak of a day when strange lights started appearing in the sky, which was sometimes followed by mysterious artifacts dropping to the surface. Some of those artifacts proved useful, and the tribes started integrating them into their culture, creating a somewhat Mad-Max like world. Nobody on planet has ever seen, let alone interacted with one of those aliens.
What could cause multiple spacefaring civilizations to be locked in a centuries-long space battle around a barren piece of rock settled by relatively primitive people, with none of them ever gaining the upper hand and claiming what ever prize it is they are after - or even interacting with the natives?
- I'd prefer multiple factions of "aliens" with different, mostly incompatible flavors of technology.
- It would be quite cool if I could drop subtle hints that the planet in question is Earth, many million years into the future, and the "aliens" are descendents of human space expeditions, but barely recognizable because of genetic drift, bio-engineering and/or cybernetic modifications.
EDIT: Some extra criteria as per bilbo_pingouins suggestion:
- All else equal, harder scifi wins. Not that important though, since from the native's perspective it all looks like magic anyways. But I'd like it if the audience could recognize some of the artifacts.
- The bigger the variety of usable equipment that makes it to the surface, the better.
- The non-interaction clause is mostly there to keep the natives from getting explanations on their artifacts (let alone a technical education), trade for spare parts or becoming, as a whole, literate enough to understand manuals and blueprints they might find. The occasional abandoned outpost, shipwreck or even stranded pilot is fine, as long as the sufficiently advanced technology keeps looking like magic.