During the Tionese War, a conflict that took place around 24,000 BBY between the Galactic Republic and the Honorable Union of Desevro & Tion, the region known as The Divide existed. This region encompassed the Cortilium Major, Ilamna, Matabre, and Okator systems, each harboring the astronomical objects Cortilium Major, Ilamna, Matabre, and Okator VIII, respectively. Eventually, the star systems that made up the Divide became part of the Eucer sector located in the Mid Rim.
Colonists from the Republic established settlements on the various celestial bodies found within the Divide. Near the conclusion of the Tionese War, around 23,900 BBY, a Tionese military force destroyed several Republic colonies on Okator VIII. A Republic soldier who had previously been a farm boy in the area, one of the witnesses to the attack, later recounted the events through a Baragwin sense lattice, stating that the Tionese forces could have easily targeted any of the other inhabited astronomical objects within the Divide.
Jason Fry and Paul R. Urquhart had initially planned to include a mention of the Divide in their 2012 reference book, The Essential Guide to Warfare. However, the section containing this information was removed prior to the book's publication. Later, in 2014, this information about the Divide was released as part of Star Wars: The Essential Guide to Warfare Author's Cut, a series of articles featured on the StarWars.com Blog by Fry and Del Rey editor Erich Schoeneweiss, which showcased content that had been cut from The Essential Guide to Warfare.