The Battle of Balmorra was a major conflict between the Galactic Republic, the Sith Empire, and the people of Balmorra during the Great Galactic War and the period of Cold War that followed. Balmorra was a historically violent, yet ardently independent world that was renowned for its highly developed military manufacturing sector. This reputation, along with the world's strategic positioning, attracted the attention of the Sith upon their return to the known galaxy in 3,681 BBY. Early in their war against the Republic, the Imperials resolved to take control of Balmorra's manufacturing capabilities, and so launched an invasion of the world that killed numerous citizens and displaced hundreds of others as refugees. In response, the Balmorrans organized a resistance group to fight against the invaders and maintain their political independence.
Recognizing the threat posed by a Sith-controlled Balmorra, the Galactic Republic dispatched military and Jedi forces to aid the Balmorran Resistance. Although the relief effort was maintained for a length of time, the continuing war elsewhere in the galaxy forced Republic Military leaders to reassign the units that were fighting on the world. As their allies gradually pulled out of the conflict, the Balmorran freedom fighters were left to battle the Empire largely on their own—a battle that resulted in the Empire gaining control of the planet's industries. Even as the Great Galactic War came to a close with the Treaty of Coruscant, the Resistance continued to fight the Sith, and even did so with the covert aid of an illegally operating Republic contingent. After several years of this guerrilla warfare, the Republic began to once again ramp up its military presence on Balmorra, thereby pushing the limits of the Treaty of Coruscant in an effort to free the world's workers from Sith servitude.
During their invasion of the galaxy the Sith Empire targeted Balmorra for capture due to the planet's reputation as a prolific manufacturer of droids and weaponry. The Galactic Republic committed itself to the defense of Balmorra, as it was a historically loyal world, however the Sith onslaught proved to great to defend against, and Republic forces were gradually withdrawn from the battle. During the initial Sith raid on the planet, a Mirialan droid designer was caught in the cross-fire and killed. Hundreds of Balmorrans were forced from their homes and made into refugees from the war. The Republic unit Havoc Squad and the Jedi KnightAryn Leneer participated in this battle.
Around the time of the Alderaan peace conference, the Republic's Demolitions Squad 419 was captured by Sith forces on the planet. Jedi KnightFortris Gall, who had been formulating their rescue, went ahead with his plan despite the official end of the war with the Treaty of Coruscant. Gall's actions forced the Republic forces under GeneralBuryn to remain on the planet past the deadlines set forth by the Treaty. As a result, the Empire resumed their attack, and the battle was put back into full swing. During the Cold War, the Republic once again built up enough strength to engage the Empire fully on Balmorra, however the people of Balmorra still felt as if they had been abandoned by the Republic during the Great Galactic War.
During the early days of the renewed war, the Republic sent a military force to Balmorra, which had been occupied by the Empire since the first Great Galactic War. Together with the Balmorran Resistance, the Republic was able to force the Empire offworld and reclaim the planet, giving the Republic access to Balmorra's weapons factories. Amongst the Balmorran Resistance members was a Twi'lek named Zenith. When a powerful Jedi Consular that was the third Barsen'thor of the Jedi Order arrived on the planet to assist the Rift Alliance and free the planet from Imperial control to convince the Rift Alliance to join the Republic, Zenith allied with the Barsen'thor and together they journeyed through the planet, slaying Imperial forces everywhere. At last, the duo reached Darth Lachris, the Sith Lord in control of Balmorra. As the governor of Balmorra, Lachris was supported by other Sith and Balmorrans. The Sith Lord Darth Minax, also with Lachris, would suffer the same fate when Lachris was slain by the Barsen'thor. With Lachris, Minax and the Imperial forces destroyed, Balmorra was safe from Imperial power once again.