This lore can be found on Hutta.
While no written record exists concerning the Evocii prior to the Hutts’ arrival, it is known that they were a simple and primitive species with a tribal society. When the Hutts discovered Evocar–the planet that would become Hutta–they bartered with each tribe individually, offering wondrous technology in exchange for land until they effectively owned the entire planet. Those Evocii who had refused to sell their freedom were herded onto ships and relocated to Nar Shaddaa, where they were kept as a ready source of cheap labor. The Hutts’ dominion over the Evocii continued unchallenged for centuries until a charismatic Evocii named Ejal led an uprising against the Hutts. Ejal’s revolt gained unprecedented momentum until he was betrayed by one of his tribesmen and delivered to his foes. Ejal met a gruesome end while the traitor was awarded his freedom and showered with riches. Even today, the Hutts are fond of this tale, as it reminds the Evocii of the rewards for obedience… and the price of defiance.