First Great Schism The First Great Schism was one of the first splits between followers of the Jedi Order and those who refused to follow the Jedi hierarchy ' s dictates . To its contemporaries it was a conflict without name , and known as the Great Schism by historians that followed . Eventually , the Second Great Schism necessitated referring to the initial conflict as the First . Origins . For over ten millennia , a society of Force - wielders had lived in relative peace on the Deep Core world of Tython , when they decided to relocate in order to step outside the growing sphere of influence of the fledgling Galactic Republic . They had made their new home on Ossus in the Outer Rim . Already at this point , the Order had grown doctrinaire in its practices and , to some , too rigid to allow growth . A young Jedi named Arden Lyn was one such believer , and found a leader in fellow disgruntled Order member Xendor . Xendor , a Kashi Mer , had grown vocal in his criticism of what he perceived as the Order ' s increasingly exclusionary ways . Xendor initially petitioned the leaders of the Order to depart Ossus in order to create a new academy . There , he hoped to teach and study alternative traditions of the Force , such as Dai Bendu , the Palawa , the Way of the Dark and the Protectorate of the Hidden , to name just a few . The leaders of the Order refused Xendor ' s request , but he exited in defiance despite their decision . Schism . A new academy . Xendor and Lyn departed Ossus to establish their new academy on Lettow . They would not be the only ones to defy the dictates of the Order ; larger and larger groups left Ossus to join Xendor ' s new group and study mysteries of the Force that had been forbidden to them under the Order . Eventually , Xendor ' s followers would come to be known as the Legions of Lettow . The newcomers to Xendor ' s academy pledged their allegiance to him and to the protection of their new order . They swore to defend their right to pursue knowledge of the Force without the oversight of the Jedi hierarchs , deeming them unfit to dictate which avenues were correct and which were forbidden . The Legions of Lettow initially wished to be left alone by the Jedi , but the peace would not last . The Jedi Order branded the Legions as dissenters , and both sides began to arm themselves for the conflict that had become inevitable . Open war . The truth of which side began the war is lost to history , but one of the first battles was fought on the Jedi capital world Ossus . Claiming to wish to end the conflict early and prevent it from spilling into the Republic , Xendor led the Legions in an attack on Ossus . Their attack failed , and the war continued unabated . Lyn claimed , millennia later , that Xendor tried to alert the young Republic to the threat he believed the Jedi posed to them ; that they would guise themselves as protectors and guardians while they secretly schemed for power . In this , too , Xendor failed , and the Legions failed to gain any traction in the Republic against their Jedi enemies . The conflict spread across a number of worlds as it intensified . War spread to Chandrila , Brentaal , the Republic capital Coruscant , and Metellos as well , before a significant battle on Columus . At Columus Xendor engaged the Jedi Awdrysta Pina , known by his nickname Green Blade , and was slain in single combat . Lyn would later muse that both she and Xendor had admired Pina as a free - thinker in his own right ; one who preferred to travel to unknown places in search of mysteries of the Force unknown to the Jedi Order . Ultimately , however , Pina believed that the order and structure that the Jedi represented were the foundations of civilization itself and so he stood with them rather than with Xendor . The Jedi forces commanded by Pina held a unique advantage over the Legions which even Lyn was forced to admit : their dedication to order allowed them to subsume their individuality into a larger collective and fight as one – not unlike the Force ability known as battle meditation . Xendor ' s followers refused to embrace any such tactic , believing it insectile and an affront to individuality . Extermination of the Legions . Victory over Xendor , however , was not sufficient for the Jedi to declare victory in the war . Instead , forces under Pina were sent to Lettow to attempt to exterminate the last of Xendor ' s followers . A fierce battle was fought , allowing just enough time for the last survivors of the Legions to flee beyond the boundaries of Republic space . Lyn was eventually cornered by Pina on Irkalla , after fleeing into regions of space unknown to all but Xendor . The two engaged in a duel in which she was disarmed . Unwilling to concede defeat , she channeled her strongest emotions – rage and sorrow , love for Xendor , and despair over what she believed had been unfairly taken from them – through the Kashi Mer talisman , destroying Pina ' s sword and mortally wounding him in the process . In his dying breaths , he drew on his own unique Force talent , Morichro , to defeat Lyn . The spell , in essence , placed her into a deep stasis . She would not be resuscitated until the era of the Great Jedi Purge , over 24 , 000 years later . Aftermath . The Jedi Order withdrew back to Ossus in the Great Schism ' s aftermath . Thereafter , few in the Core Worlds gave the Jedi much thought , though unbeknownst to them , the Jedi acted as the Republic ' s secret defenders on the Rim , working quietly to check the ambitions of the Hutts towards vulnerable colonies in the Slice , and keeping the militaristic states of the Tion Cluster divided . They would not declare themselves to the Republic again until the Tionese War , nearly 500 years later . Behind the scenes . For many years , it was believed that the First Great Schism was the event that resulted in the formation of the Sith Order , with Naga Sadow ' s entry in " The New Essential Guide to Characters " somewhat confirming that , saying that Sadow was the first Sith Lord in 20 , 000 years to reestablish contact with the Republic . However , Lucasfilm had intended the Hundred - Year Darkness as the event which lead to the establishment of the Sith Order , and was retconned as such in " The New Essential Chronology " . Dan Wallace , who worked on both projects , has since stated that the Naga Sadow entry was an error .