A conflict unfolded on the planet of Mantooine shortly prior to the outbreak of the Galactic Civil War. Due to insurgent actions within the Atrivis sector, the Galactic Empire deployed a garrison to Mantooine. Nevertheless, this outpost was inadequately fortified, leading to an assault by the local resistance force, the Mantooine Liberators. The insurgents triumphed, seizing control of the base and appropriating its armaments and resources. Subsequently, the Liberators occupied the former Imperial stronghold and announced their triumph, oblivious to the presence of an Imperial armada in the adjacent Fest system. This fleet had been observed by the Fest Resistance Group, the anti-Imperial organization on Fest; however, due to intricate historical circumstances, the Mantooine Liberators lacked communication with Fest. The Fest Resistance was unable to alert Mantooine, and the Liberators suffered heavy losses from the Imperial assault force. In the wake of this catastrophe, the two factions resolved to unite against the Empire, establishing the Atrivis Resistance Group. Eventually, this group became one of the initial resistance movements to align with the Alliance to Restore the Republic.