The Volsinii's ancestors were taken to P7J-989 by the Goa'uld Karun, where he ruled over them for centuries. It is unknown exactly why Karun put the people on the planet, because P7J-989 had few natural resources.
After centuries of oppression, the Volsinii revolted against their "god." This event was called the "War of the Gods," and may have involved an attack by another Goa'uld. Karun was defeated and abandoned the planet, along its people.
Now free from enslavement, the Volsinii started to develop their own civilization, eventually developing into an advanced society capable of great technological feats. The Volsinii's negligence of the negative impact their technology had on the environment eventually led to a planetwide chemical disaster, which was named Karun's Shroud after the evil ruler of their history. In order to preserve themselves, several Volsinii entered a sealed dome facility, placing themselves in stasis pods to await the renewal of their world. To ensure their welfare, they placed the android Keeper in charge of their care while they resided in the virtual environment. This plan was upset when the Keeper decided that the Volsinii would only ruin their world again if released back into the regenerated planet. (RPG: "Friends and Foes: Stargate Season Two") (SG1: "The Gamekeeper")
After 1022 years, the planet had long since fully recovered from the disaster. In 1998, SG-1 visited the planet after the discovery of the Volsinii dome facility. After a brief imprisonment by the Keeper, wherin they revealed to the Volsinii while in the virtual reality that the planet had recovered, the Volsinii escaped their confinement, and the virtual reality pod building, so as to experience the planet again. Stargate Command supplied the Volsinii with supplies and helped them build up their civilization again. This relationship flourished for years, and the people of P7J-989 eventually lent their assistance to the SGC by supplying a number of their pods for use in virtual training programs for new military additions to the program. (SG1: "The Gamekeeper")