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I am looking for the name of this series.
It starts with an intelligent ship and a crew of engineers that get a planet ready for colonization. After all of the engineers die the ship remains in space and watches the humans that were seeded on the planet. The humans on the planet know nothing of technology and come up with their own religions and customs similar to medieval times on Earth.
The book starts out as scifi but kind of descends into a fantasy series sprinkled with scifi.