The Super Galactic War was a multi-Galactic military conflict which involved a majority of the Galaxy's nations, including all of the great powers, organized into two opposing military alliances: the Allies and the Axis. The war involved the mobilization of over 100 million military personnel, making it the most widespread war in Galactic history. In a state of "total war", the major participants placed their complete economic, industrial, and scientific capabilities at the service of the war effort, erasing the distinction between civilian and military resources. Over seventy million people, the majority of them civilians, were killed, making it the deadliest conflict in Galactic history.
The start of the war is generally held to be in September 239 ABY with the Republic invasion of Korriban and subsequent declarations of war on the Killistian Republic by the Mandalorian Empire and Dantooine. Many belligerents entered the war before or after this date, during a period which spanned from 237 ABY to 241 ABY, as a result of other events.
The Yuuzhan Vong and the Dathomiri Empire emerged from the war as the world's superpowers. This set the stage for the War of No Conflict, which lasted for the next 45 years. The Union of Worlds was formed in the hope of preventing another such conflict.
Background[]
In the aftermath of the Trench War, a defeated Republic signed the Treaty of Pacification. This caused the Republic to lose a significant portion of its territory, prohibited the annexation of other states, limited the size of Republican armed forces and imposed massive reparations. The Yuuzhan Vong's civil war led to the creation of the Yuuzhan Vong Empire which soon was under the control of a single High Priest. On Bespin, Benvol Kirust seized power as a fascist dictator promising to create a "New Galactic Empire."
Gregor Killist, after an unsuccessful attempt to overthrow the Republican government in 223 AbY, became the Supreme Chancellor in 233 ABY. He abolished democracy, espousing a radical racially motivated revision of the world order, and soon began a massive rearming campaign. This worried Dantooine and the Mandalorian Empire, who had lost much in the previous war, as well as Bespin, which saw its territorial ambitions threatened by those of the Republic. To secure its alliance, Dantooine allowed Bespin a free hand on Dxun, which Bespin desired to conquer. The situation was aggravated in early 235 ABY when Killist repudiated the Treaty of Pacification, speeding up militarization and introducing conscription. Hoping to contain the Republic, the Mandalorians, Dantooine and Bespin formed the Stama Front. The Yuuxhan Ving, concerned due to Killist's goals of capturing vast areas of the Outer Rim, concluded a treaty of mutual assistance with Dantooine.
Before taking effect though, the Danto-Vong pact was required to go through the bureaucracy of the League of Planets, rendering it essentially toothless and in June 235 ABY, the Mandalorians made an independent naval agreement with the Republic easing prior restrictions. The Dathomiri, concerned with events that were unfolding, passed the Neutrality Act in August. In October, Bespin invaded Dxun, with the Republic being the only major power supporting the invasion. Bespin then revoked objections to the Republic's goal of making Alderaan a client state.
In direct violation of the Treaty of Pacification, Killist remilitarized the Mid-Rim in March 236 ABY. He received little response from other powers. When the Naboo Civil War broke out in July, Killist and Kirust supported fascist General Tippo's nationalist forces in his civil war against the Ving-supported Naboo Royalty. Both sides used the conflict to test new weapons and methods of warfare and the nationalists would prove victorious in early 239 ABY.
With tensions mounting, efforts to strengthen or consolidate power were made. In October, the Republic and Bespin formed the Cloud City-Coruscant Axis and a month later the Republic and the Dagasese Empire, each believing the Yuuzhan Vong Empire to be a threat, signed the Anti-Yuuzhan Pact, which Bespin would join in the following year.