Dathomir was colonized a few times by different species and groups, but the colonists kept disappearing. This was likely due to the large population of Ranocrs there that liked to assert their place at the top of the food chain by eating everybody else. Evenually a small Human civilization began there, but it faced continuous hardship and lived in constant fear of being eaten. That all changed when a bitch came to town. She enslaved all the males and used the Force to tame the Rancors. That bitch's descendents continued to rule the planet and became known as the Bitches of Dathomir. Many years later, Han Solo won the planet in a card game, but he turned over rulership to one of the bitches, since he didn't really need that planet.
Tenel Ka was born on Dathomir. Her mother was a bitch.