From the develop blog, we have some very interesting info about Manaan. The Shuuru Datalog details as follows:
It is not a foolish endeavor to try and anticipate one’s future path, or even the path of an entire civilization. But it can be. If we do not first take stock of that which lies in our wake, we can never truly know how to negotiate the currents ahead. It is with this concern in mind that I indulge in this analysis of the ebb and flow of my dear home, Manaan.
For a long time–longer than we have records for–the Infinite Empire ruled our world. They enslaved us until their eventual fall, and we Selkath vowed we would never be placed in servitude again. As offworld explorers eventually arrived on our world, they came to see our kolto as a vital resource in their contest for dominion over the galaxy. We in turn came to see how valuable kolto could be. Due to our history, however, we also saw how it could become a detriment.
From here they continue to tell us the story of their ancestors. They wanted to remain neutral in this galactic war so they even allowed both the Galactic Republic and the Sith Empire to establish embassies on their surface metropolis, Ahto City. They thought all was well, until a Jedi named Revan visited.
He exposed a terrible truth–that the Sith were abducting and manipulating our youth, indoctrinating them into the ways of the dark side of the Force. This revelation did not sit well with my ancestors, and the resulting tensions eventually sparked an uprising led by one of those abducted children, Shasa–by this point a powerful Force practitioner in her own right.
And then, all of the Sith were evicted from Ahto City. Manaan had now chosen a side, even if it was unintentional in the beginning. They continued to do business with the Republic.