During the nascent stages of the uprising against the Galactic Empire, the rebels Kanan Jarrus and Sabine Wren embarked on a quest that took them to the third moon of Concord Dawn. Jarrus's objective was to forge an alliance with Fenn Rau, the leader of the Protectors who governed Concord Dawn, ensuring the rebels could navigate the Concord Dawn system without incident. Alternatively, should negotiations fail, his aim was to neutralize the Mandalorians' Fang fighters to prevent attacks on the rebel fleet as it traversed the system. Meanwhile, Wren leveraged the tenets of the Mandalorian code to challenge Rau to a duel, seeking retribution for the injuries he inflicted upon Captain Hera Syndulla during a dogfight above Concord Dawn. The endeavor proved fruitful; the rebels successfully captured Rau, compelling him to grant them passage through his territory.
In the year 3 BBY, the Phoenix Cell made the decision to create a fresh route through the Lothal sector. Acting on the advice of the Mandalorian Sabine Wren, the rebels journeyed to the Concord Dawn system with the intention of securing safe passage from the Mandalorian Protectors, a Mandalorian group that had sided with the Galactic Republic during the Clone Wars. However, the Protectors, under the command of Fenn Rau, had pledged allegiance to the Galactic Empire and attacked a rebel delegation headed by Phoenix Leader Hera Syndulla.
Hera suffered severe wounds in the assault. Consequently, the rebels abandoned diplomatic efforts and began considering military action against the Protectors. Sabine successfully located the Protectors' Fang fighters at a base located on the third moon of Concord Dawn. Sabine argued for the destruction of the Protectors' starfighters to eliminate the threat they posed to the rebellion. The Jedi Kanan Jarrus concurred with Sabine's strategy but insisted on undertaking the mission solely with the astromech droid Chopper, who piloted the Phantom, a supplementary starship. Secretly, Kanan planned to re-engage in negotiations with Fenn Rau, offering the Protectors a second opportunity to join the rebellion as allies.
As they neared the Concord Dawn system, Chopper alerted Kanan to the fact that Sabine had secretly boarded the Phantom. After revealing herself, Sabine and Kanan debated their differing viewpoints. While Sabine was determined to avenge the harm Fenn had inflicted on Hera, Kanan remained committed to finding a peaceful resolution to the conflict. Ultimately, Kanan permitted Sabine to destroy the Fang fighters only if his attempts at peace talks with Fenn proved unsuccessful. Chopper dropped the two rebels off near the Protector's camp on Concord Dawn's third moon before returning to the skies. Upon landing, Kanan and Sabine observed the Protectors receiving provisions from an Imperial shuttle.
While Kanan pursued Fenn Rau into a structure, Sabine made her way to the starfighter airfield and began placing explosives on the Fang fighters. Fenn quickly detected Kanan's presence and allowed him to reveal himself. In an effort to build a connection with Rau, Kanan identified himself as a survivor of the Great Jedi Purge who had participated in the Third Battle of Mygeeto. Rau had commanded Skull Squadron during that battle and had saved the lives of Kanan, his deceased Master Depa Billaba, and numerous Clone troopers. Kanan then attempted to persuade Rau to realign the Protectors with the rebellion. However, Fenn refused, believing that the rebels had little chance of succeeding against the Empire.
Simultaneously, Sabine managed to attach explosives to seven of the Fang fighters before being discovered by two Mandalorian sentries. After identifying herself as a member of Clan Wren (an adversary of the Protectors), Wren invoked her right to seek justice through combat. Kanan's negotiations with Fenn were disrupted by news that his men had apprehended another intruder who had invoked the rite of justice through combat, an ancient Mandalorian custom that had not been exercised during the Age of the Empire. Fenn led a reluctant Kanan to the airfield where the duel was scheduled to take place.
Despite Kanan's pleas for restraint, Sabine remained resolute in her plan and urged the Jedi to trust her. Before the duel, Sabine condemned Fenn for attacking and injuring Hera. Rau admitted to attacking Hera but maintained that it was not personal. As Fenn drew his blaster pistol, Sabine shot it out of his hand and detonated seven of the Fang fighters using her explosives. Kanan and Sabine then exchanged gunfire with the Protectors during the ensuing conflict. Meanwhile, an enraged Fenn boarded the remaining Fang fighter and attempted to attack the rebel fleet.
However, Kanan managed to latch onto the starfighter as it ascended into the skies. Despite Fenn's attempts to dislodge the Jedi intruder, Kanan managed to use his lightsaber to slice through the cockpit and disable the control console. Meanwhile, Sabine rendezvoused with Chopper, and the two flew into the skies to retrieve Kanan. Following a physical altercation, Kanan managed to knock the Protector of Concord Dawn unconscious and carry him onto the Phantom.
Once aboard the Phantom, the three rebels returned to join the Phoenix fleet in space. As soon as Rau began to regain consciousness, he was contacted via comlink by his men. Kanan ordered Fenn to answer the comlink. By that point, the Protectors had gathered reinforcements and were preparing to pursue the rebel intruders. However, Fenn ordered them to stand down and grant the rebels safe passage through the Concord Dawn system. He also instructed them to conceal his capture from the Empire.
Fenn Rau accompanied Kanan and Sabine back to the Phoenix fleet, where he was taken into rebel custody. Due to his combat prowess and training, the rebels viewed Fenn as a "reluctant recruit." Fenn himself considered the arrangement an "alliance of necessity." Sabine's actions during the mission earned her praise from Hera, who commended the younger rebel for finding a satisfactory solution to the Concord Dawn impasse. By demonstrating their strength, the Phoenix rebels were able to establish a new route to the Lothal sector that passed through the Concord Dawn system.
The mission to the third moon of Concord Dawn served as the culmination of the Star Wars Rebels episode "The Protector of Concord Dawn," which premiered on Disney XD on January 27, 2016.