Around the time of the Battle of Yavin, the Galactic Empire established a presence on the remote planet Dathomir. While Emperor Palpatine was aware of the presence of the Force-sensitive Witches of Dathomir, he allowed the construction of a prison on the planet. Imperial troops initially encountered no resistance from the Witches, and focused their efforts in hunting the Kwi that were brought to near extinction.
When the construction of the Imperial prison was completed, it was not long before the Nightsisters, a sect of evil Dathomiri Witches, approached the Imperial commander. Their leader Gethzerion offered the services of her clan to control prisoners. Although the commander was quite suspicious about her true intentions, he finally accepted her offer. Gethzerion and her dark minions thus became a familiar sight in the Imperial compound. Using the dark side of the Force, the Nightsisters began to corrupt the Imperial troops and progressively usurped control of the prison staff from Imperial officers.
When the Imperial commander discovered the situation, Gethzerion and the Nightsisters turned Imperial troops against their officers. A battle therefore erupted on Dathomir between loyal Imperial forces and the Nightsisters backed by their Imperial slaves. Eventually, the Nightsisters were defeated and repelled from the prison.
As the Emperor realized that Gethzerion and the Nightsisters were more powerful than what he expected, he ordered the Witches of Dathomir to be confined on their planet. Shortly after the Battle of Yavin, Captain Zsinj bombarded the Imperial prison from orbit, destroying every vessels parked there to prevent the Nightsisters to leave Dathomir. All communication equipment present on the planet was also destroyed. Dathomir was blockaded by Imperial starships with strict orders to never land on the planet. The prison and all Imperial forces at the surface were abandoned. These troops continued to fight the Nightsisters for years, but they eventually became slaves for Gethzerion and her dark followers.
- The Dark Side Sourcebook
- "Who's Who in Star Wars Galaxies" — Star Wars Insider 65
- Geonosis and the Outer Rim Worlds