[Astromancer]

Try this one...

The old ones say seven peoples came on the sky ship. Six peoples including ours went to the great northern land. The seventh people went to the southern isles. The six peoples in the north warred with each other and lost all, their tools, their skills, their future.

The cunning folk of the southern isles stayed at peace and bent themselves to hard work. They soon recovered the path to the skies. They built cities on the moons, the old ones point out the lights of their cities, like stars in the wrong places. They crossed between the stars again but took no thought to those whose ancestors traveled with them.

Now the folk of the Southern Isles have joined a confederation of peoples across the stars. They send their "Anthropologists" to study the failed ones, the primitives.

Basically, the PCs are either coming to study people who fell into a new barbarism or they are the descendants of those who destroyed their future and traped their children and their children after them. Some of these coming to study the "Fallen" are serious scholars others are thrillseekers, both types gall the people stuck in primitive poverty.

In each category, there are conflicts within each group. Some of the South Islanders see the Northerners as a necessary control group. They live as humanity lived through most of its history. Other Southerners want to aid the Northern folk out of primitive poverty. Among the Northerners, some bitterly resent being left behind while the Southerners travel the stars and live millennia-long lives of luxury, others believe they have preserved their faiths and their integrity, they see the wealth and luxury of the Southerners as a deadly corruption. Some would work with the Southerners others would kill or rob them, still others simply scorn them.