Prequel to Dune: the Butlerian Jihad
"I am not sure that Frank Herbert meant any paticular 'Butler.' But he was certainly referring to the Luddite anti-machine uprising in Britain at the beginning of the industrial revolution.
"As to the story of the aborted female fetus in the Dune Encyclopedia which brought about the Butlerian Jihad, that creation was entirely my own, as I recall, and I named her 'Jehanne' after Joan of Arc — the warrior saint.
"I had proposed to Frank Herbert that he and I collaborate on a prequel to the Dune saga called Prequel to Dune: the Butlerian Jehad or some similar title. Frank Herbert and I had discussed writing it together and he agreed with my general plot outline, completed first chapter, and so on but his untimely death prevented us from continuing. He had been living in the LA area at the time and we often discussed it by phone, but I have no written notes from him about it, unfortunately. The prequel would have followed in general terms the story as outlined in the Dune Encyclopedia — sketched in my notes — which I still have — and written in final published form by one of my colleagues at Cal State."
-- Dr. Willis E. McNelly, 1999