The Tionese War, which can also be referred to as the Tionese Wars or the Republic-Tionese wars, marked a significant galactic conflict. This war pitted the Galactic Republic and the Hutt Empire against the Honorable Union of Desevro & Tion from approximately 24,000 to around 23,900 BBY. Following the decline of Xim's empire over a millennium, the Tion Cluster had largely devolved into a disunited and underdeveloped region. Leaders within the Cluster believed that rapidly conquering the Republic and seizing its technological advancements would be their only path to salvation. Without any prior warning, the Union launched an attack on the Republic, catching them off guard and resulting in initial defeats for the Republic. However, due to its superior industrial capabilities and the assistance of the Jedi Order, the Republic eventually managed to subdue Tionese territories after a century of fighting.
After Xim the Despot's defeat in the final battle of his wars against the Hutt Empire a thousand years prior, his empire had splintered into numerous warring factions. The Tionese civilization, consistently threatened by the Hutts, suffered from both technological and cultural regression. Furthermore, a devastating Hutt invasion of their colonies within the Kiirium Reaches, known as the Devouring, occurred when the Hutts sought to prevent a Tionese alliance with the burgeoning Republic. This invasion rendered the Kiirium Reaches uninhabitable, transforming it into a barren expanse known as the Ash Worlds.
Around 25,000 BBY, several Core Worlds joined forces to establish the Galactic Republic. Republic scouts, advancing rimward along the Perlemian Trade Route, soon encountered Tionese ships. Following initial interactions between Republic traders and Tionese nobles, the Tionese became aware of the Republic's advanced technology, but also its lack of a strong military. The rulers of Desevro viewed the Republic as a vulnerable target ripe for conquest, and convinced the other Tionese states to form a loose confederation with the express purpose of conquering the Republic.
Despite warnings from the Jedi Order (then stationed on Ossus) regarding the growing Tionese warfleets, which utilized reverse-engineered Republican technology, the Republic disregarded these warnings. Consequently, the Republic was completely unprepared when the Tionese initiated their offensive.
The initial Tionese attack, launched along the Perlemian Trade Route, faced minimal opposition. The Tionese captured Abhean, Roche, Lantillies, and Tirahnn before the Republic could effectively mobilize and construct its own warfleet. Tionese raiders utilized a new weapon – pressure bombs – to destroy the shipyards of Axum and Perlemia, before deploying these bombs against Alsakan and even Coruscant.
Following a desperate counterattack that successfully repelled the Tionese offensive, the Republic launched new warships from shipyards located at Corellia, Rendili, and Humbarine. For almost a century, offensives and counteroffensives raged up and down the Perlemian. Republic operatives successfully manipulated the Hutts into attacking the Tionese border, and eventually the Jedi entered the war, leading Republic forces in an attempt to prevent galactic civilization from descending into barbarity.
With the Republic's immense industrial capacity fully engaged in the conflict, the Tion's defeat became inevitable. Convinced that their culture faced annihilation, the Tionese resorted to covert and suicidal attacks, devastating even remote colony worlds within the Divide. One such attack, on Okator VIII during the war's final months, left only one survivor.
These tactics only served to infuriate the Republic, leading its leaders to adopt a policy of total war. Key Tionese planets were bombarded with pressure bombs, and ultimately Desevro itself faced destruction under the guns of the Republic Navy. Desevro's attempt to unconditionally surrender was rejected. The Republic's leadership was determined to sterilize the planet in order to force the remaining Tionese to surrender. The Jedi Order strongly opposed this action, and after tense negotiations in orbit of Desevro, a compromise was reached where the Jedi would serve as Watchmen over the Tionese worlds to prevent any recurrence of the war.
The war with the Republic signified the end of the Tion's prominence as a galactic power. By approximately 23,900 BBY, the worlds of the now-defunct Union joined the Republic as a member sector. Within a few centuries, the Tion was reduced to just another sector within the Republic.
Appalled by the sterilization of Desevro, the Jedi subsequently distanced themselves from the Republic, although the Order agreed to defend the Republic's frontier from their bases near the Tion, monitoring the cluster from fortress worlds such as Falang Minor.
Despite the Republic's victory, the military's fanatical conduct during the war led the Core regions to perceive a centralized military as a threat to the Republic's stability. Over the objections of the Jedi and many Rimward systems, the standing military was reduced in size; the majority of the Republic's military forces were reassigned to local sector governments, and a centralized federal navy would not be re-established until 15,000 BBY.
