In the year 3653 BBY, the Galactic Senate of the Republic gathered to select a successor to the Supreme Chancellor, the leader of their democratic system. Following the murder of the previous office holder during an attack on the planet of Coruscant by the Sith Empire, Cerean Senator Paran Am-Ris temporarily oversaw the Senate's operations. When the moment arrived for the formal Chancellor election, the Senate members unanimously chose Senator Dorian Janarus from Coruscant, recognizing his effective leadership on the planet in the wake of the crisis.
By 3653 BBY, the Galactic Republic had been engaged in the Great Galactic War against the Sith Empire for several decades. The Empire brought the war to an end with a sudden offensive. While Republic's military forces were deployed to the outer reaches of the galaxy and envoys from both sides were negotiating a peace treaty, Imperial forces invaded the Republic's capital world, Coruscant. The Sith quickly gained control of Coruscant. The Jedi Temple was pillaged, Supreme Chancellor Berooken was killed, and the devastated ecumenopolis was held for ransom by the Sith. This forced the Republic's peace delegation to sign the Treaty of Coruscant, which divided the galaxy between the two powers and abandoned allies in the outer regions in order to cease the conflict. This led to a Cold War between the two factions. Senator Paran Am-Ris of Cerea was appointed as the interim Chancellor until a formal election could be conducted.
Senator Dorian Janarus had served as Coruscant's representative in the Galactic Senate for many years, dating back before the Sith Empire's emergence in 3681 BBY and the start of the Great Galactic War, but the war elevated his profile. Although he found his position satisfying, he harbored ambitions for the Chancellorship and its associated prestige. Having survived the Sacking of Coruscant, Janarus assumed leadership in the aftermath, assessing the damage and coordinating aid to those in need. His actions earned him recognition as a strong leader, not only among the Coruscanti but throughout the Republic.
The people of Coruscant and the Republic's political figures were filled with hope due to Senator Janarus's leadership. The thousands of representatives within the Galactic Senate cast a unanimous vote to elevate Janarus to Supreme Chancellor. He then succeeded Am-Ris, beginning his four-year term in office.
In the years following his election, Janarus's popularity diminished as the costs of rebuilding Coruscant mounted, straining the economies of many of the Republic's representative star systems. He also faced disapproval from the military, who resented his reluctance to address sedition within the government. Despite these challenges, Janarus secured re-election in 3649 and 3645 BBY. These elections were subdued due to fears of assassination by the Sith Empire.
Dorian Janarus played a significant role in Star Wars: The Old Republic, a 2011 video game developed by BioWare. To promote the game, BioWare published a series of articles on the game's official website, within the Holonet section, providing background information on various topics. Janarus's article detailed his unanimous election as Supreme Chancellor, a position he held until his death in the game.