Less than 200 people squeezed into a church, had turned into 10,000 people spread across dozens of villages, 200 years later. Post apocalyptic and medieval are similar, but they got a lot more learning to hunker down on until they figure out medieval technology properly. A traveling saleswoman was handing out cheat sheets for 19th century technology to the kids from The Walking dead last year. Aquaducts, windmills, shoes, smelting, and a simple surgery guide for idiots. The people of New Eden off in the provinces are probably more reliant on what they have made, because that's all they have.