The Kostra system existed within the Romintine sector, which itself was situated in the Trans-Hydian portion of the Mid Rim. The inhabited terrestrial astronomical object Kostra was a part of this system. Sometime in the period spanning from 2 BBY to 0 BBY, Galactic Empire forces launched an attack on Kostra as they tried to put down Rebel Alliance activities. During this conflict, Imperial Senator Leia Organa journeyed to the Kostra system aboard her consular starship, the Tantive IV; this visit represented one of several instances where Organa provided logistical or communications aid to the Alliance, or deliberately created diversions for Imperial forces.
Furthermore, during the same battle, which resulted in an Imperial victory, Fulkrehm Protial, a pilot operating an Alliance Y-wing starfighter, was compelled to execute a crash landing on Kostra. In the time shortly after the Battle of Yavin, Protial, having survived the crash, proceeded to serve at the Rebel base located on the Outer Rim Territories world of Berrol's Donn.
The 2009 reference work The Essential Atlas, penned by Daniel Wallace and Jason Fry, initially mentioned the Kostra system, locating it within grid square Q-8.