Tol Cressa, identified as a male, held the esteemed position of Supreme Chancellor within the Galactic Republic during the tumultuous era of the Mandalorian Wars. The Chancellor dedicated his efforts to the Republic's recovery from the widespread destruction caused by both the Great Sith War and the subsequent Jedi Civil War. As late as 3946 BBY, Cressa remained in his office, at which time he orchestrated the successful liberation of a sector that had previously seceded from the Republic's control, under the command of renegade G0-T0 infrastructure planning system droids.
Tol Cressa, whose gender was male, achieved the high office of Supreme Chancellor governing the Galactic Republic during the period known as the Old Sith Wars. Around 3963 BBY, coinciding with the beginning of the Mandalorian Wars, Cressa assigned Jedi Master Raana Tey to a special, undisclosed mission. As the battle for the planet Taris, located within the Outer Rim, neared its end, Cressa launched an investigation into how the ecumenopolis was so rapidly integrated into the Republic. Three years prior to Cressa's investigation, Taris gained admittance to the Republic through the actions of Lhosan Industries Chairman Jervo Thalien and Haydel Goravvus, who used bribes to influence other senators to vote in favor of the planet's inclusion. Following the death of Admiral Jimas Veltraa during the battle, the Chancellor vetoed the proposal to rename an Interdictor-class cruiser in Veltraa's honor. During the Mandalorian occupation of Taris, Cressa tasked Tey with locating and assisting Goravvus, who had become the planet's senator after Taris joined the Republic. Goravvus was at the head of the Tarisian resistance efforts against the occupying Mandalorian Neo-Crusaders.
After the devastation inflicted upon the planet Duro by the Mandalorians in 3962 BBY, Cressa, bowing to the will of the Republic's populace, appointed Jedi Knight Revan—whose Jedi faction was cooperating with the Republic's forces under the cover of a mercy corps,—as the commander of the Republic's armed forces. In 3955 BBY, one year following the end of the Jedi Civil War, Cressa initiated the Telosian Restoration Project, a large-scale initiative aimed at rebuilding the planet Telos IV after its destruction during the Jedi Civil War.
During the period known as the Dark Wars, a series of conflicts encompassing the Sith Triumvirate's assassination campaign targeting the Jedi Order, Cressa also sanctioned the G0-T0 infrastructure planning system droid project, intending to facilitate the reconstruction of planets and infrastructure left in ruins by the Great Sith War—fought between the Republic and Sith Lord Exar Kun's Sith Empire—and the Jedi Civil War. The G0-T0 droids, which controlled the 400100500260026 territory consisting of sixteen planets, declared their secession from the Republic, severing HoloNet communications and blocking all traffic to and from the Gordian Reach sector. In 3946 BBY, Cressa organized a successful recapture of those planets, removing them from the control of the G0-T0 droids.
During the Mandalorian Wars, Tol Cressa demonstrated a willingness to elevate Jedi Knight Revan to the rank of commander of the Republic's military, influenced by the desires of the Republic's citizens. He also expressed his dissatisfaction with the Jedi High Council, which had adopted a policy of non-intervention in the Mandalorian Wars. In the era following the Jedi Civil War, Cressa was remembered as a Chancellor of legendary status.
The character of Tol Cressa was initially referenced in the twelfth issue of the Star Wars: Knights of the Old Republic comic series, with his backstory further expanded in The New Essential Guide to Droids. However, the Chancellor remained unnamed until the publication of the Knights of the Old Republic Campaign Guide, which identified him by his surname. He later received a dedicated entry in The Complete Star Wars Encyclopedia. The first name "Tol" was assigned to Cressa in The Essential Guide to Warfare, which also provided more detail about his involvement in the Mandalorian Wars.