The conflict known as the Battle of Dac City unfolded a single year following the establishment of the Galactic Empire. This battle commenced when Darth Vader embarked on a mission to the world of Mon Cala. The purpose of this mission was to ascertain whether a Jedi was concealed on the planet, potentially guiding the Mon Calamari ruler, Lee-Char, in his negotiations with the Empire. Wilhuff Tarkin, a Moff stationed on the Sovereign, had previously dispatched Telvar, an envoy, to broker a trade agreement with Lee-Char. However, the sovereign consistently rejected the individual, leading to Telvar's temporary withdrawal.
At that precise moment, Vader's arrival occurred, accompanied by three Inquisitors and a unit of distinguished Purge Troopers. They were met by Gial Ackbar, the king's head of security, who refuted any suggestion of a threat existing on Mon Cala. Nevertheless, the Lambda-class T-4a shuttle transporting Telvar suffered an explosion, resulting in the demise of all occupants. This incident triggered Tarkin's decision to deploy his military onto Mon Cala. Lee-Char promptly informed the Jedi about these events. The Jedi responded by stating he was capable of dealing with the Inquisitors and that he knew the identity of the dark clad figure whose name Ackbar had been unable to obtain.
Forces composed of Mon Calamari and Quarren, under the command of King Lee-Char, engaged in combat against an Imperial battalion. This battalion consisted of AT-AT walkers, AT-PD walkers, and TIE fighters. Simultaneously, Darth Vader, alongside the Inquisitors Ninth Sister, Tenth Brother, and Sixth Brother, as well as Purge Troopers, successfully secured the landing platform after eliminating numerous Mon Calamari and Quarren soldiers.
The Inquisitors made their way toward the palace. The Ninth Sister expressed skepticism regarding the notion that the Jedi fugitive would be hiding in proximity to the King. Vader countered by asserting that King Lee-Char possessed the means to contact the Jedi fugitive. The Tenth Brother speculated that Lee-Char had likely fled upon the arrival of the Imperial battalion. However, Vader sensed the king's continued presence. Drawing upon his prior interactions with the king, Darth Vader surmised that the king would not abandon his city until the conclusion of the battle.
Within the command center, King Lee-Char observed a holographic representation of the ongoing battle. Ackbar, holding the rank of Commander, informed him that the defenders were maintaining their position. However, the Empire had deployed significant forces to all of their "above ground" settlements, environments in which the Mon Calamari and Quarren were not particularly adept at fighting. King Lee-Char issued instructions for the troops to hold their ground until the evacuation was completed. Ackbar assured him that their forces would persevere and that they had already relocated fifty percent of the civilian population to underground locations.
Raddus, holding the rank of Admiral, expressed reluctance to cede Mon Cala's surface cities to the Empire, emphasizing that this was their home world. Lee-Char responded that this was a strategic withdrawal. He stated that once their populations were secure, they would deliberate on their response. He clarified that his objective was to persuade the Empire to depart without causing bloodshed on Mon Cala. He identified two potential paths: war and diplomacy.
The initial mention of the Battle of Dac City occurred in Darth Vader (2017) 13, with its depiction appearing in the subsequent comic, Darth Vader (2017) 14. These canon comics, both released in 2018, were written by Charles Soule and illustrated by Giuseppe Camuncoli.