- "For the Korunnai, there is no 'after the war.' The war is all there is. Not one of them is old enough to remember anything else. They don't allow themselves even a fantasy of peace."
- ―Mace Windu
- "Mace, the Summertime War isn't something that can be resolved in weeks, or months..."
- ―Depa Billaba
The war began almost thirty years before the Clone Wars as a disagreement over the use of Haruun Kal's jungles. The Korunnai relied on their grassers to move through, and therefore plow, the jungles to find safety for the winter, while the Balawai needed the jungles intact to harvest and export its output. The Korunnai, fiercely protective of the grassers, began guerrilla war against the Balawai, who responded in kind with air strikes to protect their financial interests. The conflict developed into a brutal all out war that began each year after the snows of winter subsided and lasted until the autumn rains began, gaining its name as the "summertime" war.
The situation worsened as the Separatist crisis brewed in the Galactic Republic. Separatist interests began to sponsor the Balawai, providing them with weapons and technology to trump the primitive Korunnai, in hopes of convincing them to join Count Dooku's movement. With the outbreak of the Clone Wars, the Separatists gave the Balawai an offer they could not refuse: the defeat of the Korunnai in exchange for control of the Al'Har system. The Balawai accepted, and Confederacy forces were quick to establish a droid garrison on Haruun Kal.
Jedi Masters Mace Windu and Depa Billaba, having learned of the Confederacy's sponsorship of the Balawai, raced to Haruun Kal to save the system from falling into enemy hands. Upon their arrival, the Jedi Masters led the Korunnai in a series of decisive victories at Lorshan Pass and Pelek Baw. After destroying the droid control center and the Separatist forces, the Korunnai and Balawai conceded under Windu's guidance to form a democratic government to provide social justice and economic stability, ending the Summertime War.
- Omega Squad: Targets (Mentioned only)
- Shatterpoint (First appearance)
- Coruscant Nights I: Jedi Twilight (Mentioned only)