Yep, they found Frank Herbert’s outlines and wrote to those to get the results they got. They are pretty interesting, especially the ones from 10,000 years before.

Rothbardian_fanatic

I had no idea there were 22 prequels. I've read all of Frank Hebert's Dune books, which seemed like a lot of Dune, but apparently it's just the tip of the iceberg.

Undisciplined

BooksAndArticles

Chronological Order of Dune Books – Dune Novels (2020)

@Undisciplined will be greatly interested. He has published his Dune book review here