Derellium was a planet located within the Cronese Mandate of the Outer Rim Territories.
A leading agricultural world of the Tion Cluster, Derellium is famous locally for its wines. Some Cronese wine collections include centuries-old Derellium vintages.
One of the original member-worlds of the Kingdom of Cron, it was absorbed into Xim's empire. After the empire collapsed, it would continue to thrive as a world of the Kingdom of Cron, eventually being part of the Cronese Mandate.
In the Galactic Republic's final years, the Tion Cluster worlds joined the Confederacy of Independent Systems and were later members of the Galactic Empire.