|Post Hutt–Xim conflict|
|Great Jedi Purge|
|Galactic Civil War|
The Kiirium Reaches were settled by Humans in ages before the rise of Xer VIII in the Tion Cluster. Xim the Despot quickly expanded his empire into these worlds between 25,120 and 25,096 BBY. The region was dubbed the Kiirium Reaches, and the lush planets Huronom and Astigone became the Seventh and Eighth Thrones of the empire.
After the defeat of Xim, the Hutts decided to make the Kiirium Reaches a buffer between the Hutt Empire and the Tion Cluster. Invoking the terms of the Third Battle of Vontor, they exterminated the Tionese to the last man, woman and child within the old borders of the Kiirium Reaches. Their settlements were vaporized, their worlds bombarded and poisoned, their histories and eventually even their names erased. The planet's name were lost and most were renamed. Xim's hyperspace beacons were destroyed or towed away for the Hutts' own purposes, leaving future explorers to find new routes through the desolation. Only the beacons and a few Tionese worlds along the Salin Corridor (known at this time as Warriors' Trace) were spared to preserve a potential Hutt invasion corridor to the Tion and make sure there were hostages to take along the way. The location of the historical Kiirium Reaches was lost and was the subject of much debate among scholars for millennia.
This region of thousands of barren worlds still bearing the invisible scars of radiation was finally called the Ash Worlds, a name so widely known that the Republic adopted it for that sector of space. The spared Kiirium star systems along the Salin Corridor were not include in the Ash Worlds. Astronomers have scoured the area searching for the remnants of a supernova or some other devastating natural event, but nothing had ever been found.
Historian Bleys Harand and his students, including his protégé Henrietya Antilles, explored the Ash Worlds and eventually provided evidence that the Ash Worlds were a remnant of the Kiirium Reaches, and the Devouring was a memory of a genocidal campaign waged by the Hutts against the Tionese.