Great Hyperspace War The Great Hyperspace War was a war fought between the Galactic Republic and the Sith Empire in 5000 BBY . The conflict encompassed the entire Galactic Republic , though the main forces focused their attention on three Republic worlds , and later took the war to the remote star system Primus Goluud , and the Sith mausoleum world of Korriban . After it overcame the initial shock of the Sith invasion , the Republic ' s armadas regrouped and annihilated the Sith Empire , forcing the Sith Lord Naga Sadow to exile himself to Yavin 4 . Prelude . The Golden Age of the Sith . After their defeat during the earliest Jedi Civil Wars , called the Great Schisms , the adherents of the dark side fled from Republic space and settled on the world of Korriban , where they ruled over the barbaric , red - skinned Sith species like gods . In time , the Dark Jedi and the remarkably Force - sensitive Sith natives interbred through the use of Sith alchemy , and became one people . The united Sith formed an immensely rich and powerful empire built upon sorcery , and dark - side - fueled technology quite possibly adapted from the scattered ruins of the earlier Infinite Empire of the Rakata . Over the centuries , the Dark Jedi exiles were forgotten by the Galactic Republic , as were all records of the Republic also lost by the Sith . The two civilizations thrived in isolation , each ignorant of the other . Discovery of the Sith Empire . During the height of the Sith Empire , two Republic hyperspace explorers stumbled upon the Sith mausoleum planet of Korriban by chance . The siblings , Gav and Jori Daragon , hoped to discover a lucrative new hyperspace route that would help them pay off their enormous debts . After stealing back their impounded ship " Starbreaker 12 " , they dialed random coordinates into their nav computer and entered hyperspace , trusting in their " luck " ( " i . e . " , untrained Force potential ) to survive the journey . Their arrival on Korriban coincided with the death of the greatest Dark Lord at the time , Marka Ragnos . The two challengers for his crown , Viceroy of Khar Shian Naga Sadow , and Ludo Kressh , were in the midst of a duel for mastery on the threshold of his tomb when the Daragons descended from orbit . Upon landing , Gav and Jori were immediately captured , and brought to the icy Sith capital world of Ziost for interrogation . After learning of the forgotten Republic , a conclave of the Sith Lords led by Kressh declared them spies and sentenced them to death , but Naga Sadow disagreed . He dreamed of vast new territories to conquer for the Empire . With the aid of his alchemically - modified Massassi Warriors , he masterminded the Daragons ' escape , and planted evidence that they had been rescued by Republic agents . Sadow moved the Daragons to his personal fortress on Khar Shian , pretending he was their ally , while simultaneously using their supposed " escape " to galvanize the Sith Lords into a war against the Republic . Keeping the siblings separated , he began to teach Gav Sith sorcery , even as he made excuses to keep his sister Jori from returning to Republic space . Kressh soon discovered Sadow ' s subterfuge , and marshaled his followers to attack Sadow ' s fortress . When Kressh ' s fleet arrived , Sadow advised Jori to flee from the battle without her absent brother , and to warn the Republic of the impending invasion , but all had transpired as Sadow had planned . Once Jori made the jump to lightspeed , he unleashed a massive force that he had previously withheld and soundly defeated Kressh , whose flagship was destroyed in the engagement . With his competition presumably dead , Sadow united the military forces of the Empire , and crowned himself Dark Lord of the Sith . Following the homing beacon he had placed aboard the " Starbreaker 12 " , Sadow began his invasion of the Galactic Republic . Meanwhile , after numerous delays , Jori managed to deliver a warning to Empress Teta of the Koros system . The skeptical empress eventually followed the advice of her Jedi councilor Memit Nadill , and that of his companions Odan - Urr and Master Ooroo . She alerted Coruscant to the impending invasion , but few heeded her warnings . The war . Sith invasion . Sadow made his base at the Primus Goluud at the Coreward end of the Daragon Trail and deployed his fleets to invade numerous Republic worlds simultaneously . Sadow knew he could not defeat the much - larger Republic Navy , and so relied on surprise and rapid early victories to carry the day . He positioned his eye - shaped meditation sphere near the red - giant star Primus Goluud and used battle meditation to aid his forces in the field . The ferocity of the Sith invasion would swiftly overwhelm the lax Republic Navy . Passing the Primus Goluud , Gav Daragon was given command of the Koros Major invasion fleet . When Gav arrived in his home system , a significant battle ensued and the Sith successfully established a foothold in the system . Sadow proclaimed Gav the " liberator " of his home system , and using the Koros Trunk Line , attacked Kaikielius and the Foerost Shipyards . Moving up the trade routes , the Sith under the command of Shar Dakhan , Sadow ' s chief lieutenant , attacked Coruscant itself , landing at the Legislative District and reached the Senate Hall where they encountered Jedi defenders . Other parts of the fleet went to Metellos , Basilisk and Shawken . Sadow undone . During the fighting at Koros Major , Gav searched for his sister at Aarrba the Hutt ' s starship repair dock , flanked by a host of Massassi bodyguards . Aarrba , a close family friend , was struck down by his guards just moments before Jori entered the chamber . Thinking Gav had killed Aarrba , she attacked her brother with a lightsaber given to her by Odan - Urr . Gav fled from his sister , and returned to his master at Primus Goluud . Without their commander , the Sith forces on Koros fell into disarray , and were defeated . Upon arrival at Primus Goluud , Gav opened fire on Sadow ' s meditation sphere , breaking the Sith Lord ' s concentration upon the distant invasion of Coruscant , thereby allowing the Republic soldiers to rally and turn the tide of the battle . The tide of the war changed for good with the discovery that Sadow used Force illusions to make his forces appear more numerous than they really were . Buoyed by this knowledge , the Republic Navy rallied at Anaxes and counterattacked at Kirrek and Thokos . At the Battle of Kirrek , Jedi Master Ooroo defeated a massed force of Massassi warriors , but sacrificed his life in the process and died in the arms of his Padawan Odan - Urr . The Republic Navy then moved to support Coruscant ' s defenses and pushed the Sith forces back to Koros Major . Facing defeat , Sadow pulled his forces back to to Primus Goluud , but was followed by Jori , Empress Teta and a large Koros fleet . Realizing that the tide of war had turned against him , Sadow abandoned his embattled forces to the leadership of Gav Daragon , and used a Sith superweapon aboard his flagship " Corsair " to implode the nearby star . Disgusted by Sadow ' s betrayal , Gav turned against his master . He transmitted the hyperspace coordinates of the Sith Empire to Empress Teta , and warned her to leave the system just before Primus Goluud went supernova , destroying Naga Sadow ' s meditation sphere , and Gav along with it . Fall of the Sith Empire . Naga Sadow managed to flee back to the Sith Empire , but a living , breathing Ludo Kressh was waiting for him in ambush . Having discovered Sadow ' s plan to assassinate him , Kressh had allowed the new Sith Lord to think him dead . His attack on Sadow ' s fortress had been a feint intended to lull Sadow into complacency , but in the end Kressh ' s complex plans came to naught . He was killed when one of Sadow ' s vessels slammed into his own during the frenzied Sith battle over Korriban . The Republic armadas arrived while the Sith fleets battled each other , and managed to annihilate them both in the cross - fire . Sadow sacrificed the remains of his fleet to ensure his own survival . Destroying his pursuers with tricks and sorcery , he limped away from the engagement aboard his damaged flagship . With Sadow fled , Shar Dakhan became acting Dark Lord . In the aftermath of the battle , Supreme Chancellor Pultimo of the Republic ordered a general invasion of Sith space . The Republic and the Jedi Order then embarked on a military expedition throughout the territories ruled by the Sith Empire , to search out all remaining Sith strongholds and destroy them . The attack was temporarily averted when Shar Dakhan ordered suicide attacks , forcing the Republic forces to retreat but many Sith killed themselves ritually , giving an advantage to the Republic fleet to win the War . Aftermath . Republic . At the end of the Great Hyperspace War , inspired by the example of his deceased Master Ooroo , the Jedi Odan - Urr founded the great museum city upon the planet Ossus . Stored within its countless libraries and vaults were ancient Jedi artifacts gathered by his fallen Master , as well as Sith artifacts collected from the wreckage of their invasion fleet . The Sith artifacts included a Sith holocron that Odan - Urr had found on a derelict Sith vessel near Koros Major . Over the centuries , Ossus grew to become the premier Jedi library , archive , and academy of the Galactic Republic . Due to her bravery and tactical brilliance during the war , the people of Koros honored their leader Empress Teta by renaming their star system after her . By way of thanks for their defense of the Republic , the Galactic Senate donated a sacred mountain on Coruscant to the Jedi Order . Beginning as a small meditative enclave , the sacred spire would become the site of the Jedi Temple , the main headquarters of the order raised after the destruction of the Great Jedi Library on Ossus during the Great Sith War . Sith . Some of the Sith were exiled to Ambria , Thule , Tund and Vjun ; others were shipwrecked to worlds like Kesh without hope to escape . Although the war decimated the Sith species , these exiles ensured the survival of the Sith traditions on these planets . Naga Sadow and his remaining Massassi Warriors fled to the remote Yavin system , and hid on its fourth moon . There , he used Sith sorcery to place his body in stasis while his warped Massassi servants slowly degenerated into barbarism . One Sith survivor , Lord Vitiate , returned to his home planet of Nathema and called eight thousand Sith Lords to meet him there . Taking control of their minds , Vitiate conducted a great ritual that consumed them , the planet ' s population , and the very Force itself , leaving Nathema as little more than a void . Thus empowered , Vitiate abandoned his mortal name and became known only as the Sith Emperor . Blaming the devastation on the Jedi , the Emperor led the remnants of the Empire in a twenty - year journey into the Unknown Regions , until they came across the forgotten Sith colony of Dromund Kaas . There , he performed dark rituals , altering the planet ' s ionosphere into an electrical storm . He rebuilt the Sith forces and bided his time , until the Republic was weakened and ready for invasion once more . This culminated in the Great Galactic War between 3681 BBY and 3653 BBY .