Kesiak, also referred to as Kesiak City, served as the ancient capital city on the planet of Thule. This location was a key Sith stronghold during the time of the Sith War, and it also housed the ancient Dark Reaper weapon.
In the early period of the Clone Wars, the remnants of Kesiak's dilapidated cityscape and its environs became the setting for the concluding phases of a campaign. This conflict saw the Galactic Republic and its Clone Army opposing Count Dooku and the Confederacy of Independent Systems. The Republic fought to prevent the Dark Reaper from being activated. Due to the Confederacy's prior control over the planet, the Droid Army was heavily stationed throughout Kesiak's streets, even manning turret towers at different checkpoints.
During the battle's final stages, Jedi Master Mace Windu successfully navigated the city's utility ducts, eliminating various droids along his path, to disable the gate mechanism that was blocking access to Kesiak. Subsequently, Anakin Skywalker spearheaded clone forces into the breach in the defenses. The Reaper, briefly activated, was then confronted and defeated by the young Jedi.
After the battle concluded, Kesiak was left as smoking ruins.