After the Great Revolt against the Thinking Machines, the Butlerian Proscriptions banned all forms of advanced computational technology and artificial intelligence. All spacecraft, dependent on AI for propulsion or to navigate through folded space, were abandoned, plunging entire planetary systems into dangerous isolation. The inevitable collapse of intergalactic commerce and communication plunged humanity into a new dark age.

Then, in 88 BG, Tio Holzman's assistant, Norma Cenva, discovered that the mind-altering properties of the spice-drug mélange induced a form of enhanced awareness and limited prescience. This ability allowed Cenva to perform the delicate calculations necessary for successful foldspace navigation without sophisticated technology.

Norma Cenva’s discovery allowed the resumption of intergalactic travel and led to the eventual establishment of the independent Spacing Guild, with her as the first Navigator.

Abba,

Do you remember when I was little, you would take me to secret meetings with Uncle Rondo?

I remember once, we met a stranger in the deep desert—a pale, water-fat man with bulging yellow eyes. But what I remember most from that day isn't him because the Fremen were there, too. It was the first time I had laid eyes upon them—so exotic and fierce.

Only now, looking back, do I begin to understand. We were there to broker a deal between the Fremen and the Spacing Guild. The Fremen were trading more spice than I'd ever seen, but for what?

I remember the Guildsman winging about pressure from the Harkonnens to improve satellite surveillance of the deep desert, and it didn't mean anything then, but it does now. The Fremen were paying the Guild to obscure their movement in the southern hemisphere—to make them disappear!

Which raises an important question: if the Fremen truly are eradicated, who pays that spice bribe now?