The Grissmath Dynasty was an interstellar government that once ruled the Meridian sector in the Outer Rim Territories. Their territories included the capital Meridian and Nam Chorios. In 750 BBY, the Grissmaths exiled political prisoners to the barren desert world of Nam Chorios in the hopes that they would die of starvation and the harsh climate. Automatic gun stations were also established all over the planet to prevent them from escaping offworld. Drochs were later introduced to the planet in a failed attempt to kill the prisoners. The descendants of the prisoners and guards would eventually become known as Oldtimers by later settlers.

At an unknown date, Meridian was reduced to a charred radioactive ball as a result of orbital bombardment by unknown groups. Soon, the Grissmath Dynasty collapsed.