The Void is it's earliest mention. Then it's seen in the books, there's no confirmation of how much time passed from it's arrival from the Void and then though.
I went and read the grimore I was thinking of, and it seems that oryx( at the time aurash im pretty sure) believed the traveler was deliberately dooming his home world. It got me thinking, do you think the traveler could actually
Be an automated weapon meant to seek and destroy any manifestation of the darkness, such as the worms on fundament.
It's entirely possible. I just don't think it likely. The Worms had a hated for the Traveler, the Worms though are just servants of the Deep. They aren't the direct evil, they're just the highest point we know currently.
They, being against the Sky, and therefore Traveler, fed Aurash's father all sorts of stories to make him paranoid. They used that paranoia to instill hatred in the Sky.