In the era of approximately 4,000 BBY, a devastating internal conflict raged across the Core Worlds planet known as Grizmallt. From this world, a number of colony ships carrying human Grizmallti evacuees departed, eventually arriving in the vicinity of Nabu, a world discovered and named by the Grizmallti around 100 standard years prior. One of these vessels experienced a catastrophic failure and crashed onto Nabu's surface, while the remaining ships successfully landed, initiating the settlement of the world by the Grizmallti. Encounters and skirmishes ensued with the native Gungan population, following which the Grizmallti established the thriving Naboo civilization.
The Grizmallti's internal strife was initially referenced within the current Star Wars canon through Nexus of Power, a 2016 sourcebook for the Star Wars: Force and Destiny tabletop game. Within the Star Wars Legends narrative, the rebellion that prompted Human flight from their original planet to Naboo and the subsequent founding of the primary metropolis of Theed eight centuries prior to the Naboo conflict, was first mentioned in the 2000 reference guide, Inside the Worlds of Star Wars: Episode I by Kristin Lund. The 2001 interactive game, Star Wars: Galactic Battlegrounds, identified Grizmallt as the originating planet for Naboo's human settlers, but omitted any mention of the rebellion, placing the colonization around 3900 BBY. Subsequently, the 2009 reference work, The Essential Atlas by Jason Fry and Daniel Wallace later indicated that Theed rose to prominence as the capital following the Era of Hardship, a civil war occurring on Naboo. Nexus of Power clarified that the civil war transpired on Grizmallt within both Legends and canon.