Dathomir was a little-known planet located in the Quelii sector of the Outer Rim Territories. It was somewhat smaller than Coruscant in size and had slightly below-average gravity, though the planetary day was close to the standard. However, the planetary year of four hundred and ninety-one days was considerably longer than the standard year of three hundred and sixty days. Dathomir was considered a temperate and beautiful planet by Human standards, with a varied terrain that included coastal lakes and tar-pits, thick forests and snow-capped mountain peaks, powerful rivers and broad savannas, small icecaps and dramatic rift valleys. By the time of Darth Plagueis, nine-tenths of the planet remained unexplored and uninhabited, with the population limited to a relatively small area along the edge one of the three main continents, a zone of uplands and river plains bounded on one side by the unsailed ocean and on the other by vast expanses of desert.
Centuries before the formation of the Order of the Sith Lords, a rogue Jedi Knight named Allya was banished to Dathomir by the Jedi Council. She took many followers with her and forged a friendship with the few settlers that were on the planet. She taught many of them the ways of the Force, and later she taught the ways of the Force to her own children. Centuries later, Allya was credited for transforming the settler society into one led by women who held their men as slaves. This society was dominated by Force-using women that became known as the Witches of Dathomir, and there were many occasions when their legends were used to scare children around a fire. The Sith Lord Darth Plagueis later encountered the Witches of Dathomir.
During the New Sith Wars, a Sith Academy was constructed on Dathomir. Located on the edge of a large canyon, the academy grounds remained a graveyard of members of the Brotherhood of Darkness that had died defending their empire during the New Sith Wars, and of those that had failed their tests of strength before the war even broke out. Rotting skeletons still laid within the forests around the academy even during the days of the Invasion of Utapau, serving as a stark reminder of the consequences of failure. Darth Plagueis used the academy as his headquarters, and he was later killed there by his apprentice, the Dark Lord.
- Darth Bane: Path of Destruction (First mentioned)
- Star Wars: Episode I - The Chosen One (First appearance)