Dathomir, nicknamed the «rancor planet,» was a remote, neutral and obscure planet in the Dathomir system of the Quelli sector in the Outer Rim Territories and New Territories of the galaxy. It was the home of the Nightsisters, Nightbrothers, Blue Coral Divers Clan, Singing Mountain, and the Howling Crag. The planet, bathed in blood-red light by its central star, had numerous continents that were overrun with vegetation, forests, and swamplands. The dark side of the Force had an immensely strong presence on Dathomir, which allowed for the nurturing of many malevolent Force wielders native to the planet. The Nightsisters, also known as the Dathomir witches, made their home in the swamps, and wielded magicks fueled by Dathomir’s own power. Dathomir was also home to the Nightbrothers, Zabraks who were ruled by the Nightsisters. It was also the homeworld of the semi-sentient rancor species.
During the Clone Wars, Dathomir would come under attack multiple times due to the machinations of Mother Talzin and her rival Darth Sidious, leading to the destruction of most of the Nightsisters and settlements on the planet by the Confederacy of Independent Systems after conquering it. Asajj Ventress, a Nightsister trained by Count Dooku, returned to Mother Talzin after her master betrayed her. This drew Dooku’s attention to Dathomir, resulting in the slaughter of the Nightsisters. This left Talzin, Ventress, Merrin, Shelish, Jerserra, and Yenna as the only known survivors.
In 2 BBY, Maul returned to Dathomir with the Jedi rebel Ezra Bridger to conduct a ritual that involved summoning the spirits of fallen Nightsisters in order to reveal fragments of a holocron vision. As a result, Maul and Ezra learned that the Jedi Master Obi-Wan Kenobi held the key to destroying the Sith and that he resided on a planet with twin suns.