Around the year 3900 BBY, a group of Humans originating from the Core World of Grizmallt initiated the colonization of Naboo. Approximately one thousand years afterwards, specifically circa 2900 BBY, the city of Kaadara was established along a picturesque coastal region in the northern territories of this Mid Rim planet. Unusually for Naboo at the time, Kaadara distinguished itself from other Naboo settlements by fostering and encouraging interactions with the indigenous Gungans. Kallos Sook, Kaadara's first regent, famously recruited a large Gungan force to function as the city's security force. However, in the centuries that followed Sook's time as regent, the increasing presence of outsiders generated distrust among the Gungans, leading them to relinquish their role as Kaadara's protectors. Subsequently, the Naboo people replaced them by stationing a small garrison of Royal Naboo Security Force officers in the city.
Kallos Sook's initial mention occurred within the 2003 video game Star Wars Galaxies: An Empire Divided. This game was a massively multiplayer online role-playing game, developed by Sony Online Entertainment and published by LucasArts. The game was eventually shut down on December 15, 2011. Sook was briefly referenced in the descriptive overview for Kaadara, a city located on the planet of Naboo.