They were two of the Five Brothers. It was believed that the Celestials moved the planets into Corell's orbit from other places in the galaxy, along with three other planets; all kept in place by the Centerpoint Station.
In 500 BBY, the Federation of the Double Worlds was founded—the government of Talus and Tralus. The Federation capital is Dearic on Talus. In 470 BBY, Corellia, Selonia, and Drall allied in an attempted coup of the Federation, but failed. The Federation was allowed a certain degree of autonomy under Imperial rule.
- The Essential Guide to Planets and Moons (First mentioned)