The Timeline

Legacy Era

127 – 130 ABY – The Sith-Imperial War

o Around this time, the Galactic Alliance, Jedi Order and Yuuzhan Vong initiate a successful terraforming of the war devastated planet Ossus. As a result, Yuuzhan Vong terraforming technology is implemented on a hundred other planets. The new Sith Order sabotages it.
o The resurgent Galactic Empire (formerly the Imperial Remnant) starts a secession movement against the Alliance.
o The Empire declares war on the Alliance at the Treaty of Anaxes.
o The Sith form an alliance with the Galactic Empire through the Director of Imperial Intelligence Nyna Calixte.
o After three years of fighting, the Alliance is defeated at Coruscant and its remaining territories are absorbed by the Empire which becomes the new galactic government. The Jedi Order is nearly destroyed during a massacre at Ossus, with Kol Skywalker as one of the casualties.
o The Sith-Imperial War ends.
o The new Sith Order turns against Emperor Roan Fel and his Imperial Knights. Darth Krayt usurps the Imperial throne, though some parts of the Empire remain loyal to Fel.

137 ABY

o Cade Skywalker, descendant of Luke Skywalker, is trained as a Jedi but self-exiled of the Order to become a bounty hunter. He begins to rediscover his destiny as a Jedi Knight and as a member of the Skywalker family, and rises to fight the new Sith. He embarks on a series of adventures aboard his starship Mynock.
o Darth Krayt is killed by Darth Wyyrlok (III) after the Battle on Had Abbadon.
o Darth Krayt is resurrected.
o A regenerated Darth Krayt kills Darth Wyyrlok (III), and re-claims his role as Emperor.

138 ABY

o In a desperate attempt to destroy the One Sith, the Fel Empire and Galactic Alliance Remnant cooperate with one another, and under the command of Jedi General Cade Skywalker along with the majority of the New Jedi Order they defeat the One Sith's forces; the coalition then further progress their counter-invasion, by hitting Coruscant with a full morale. This battle is called the Showdown at Ryndellia.
o Darth Krayt is found on Korriban, where the Jedi, led by Cade Skywalker, and backed up by the Republic/Imperialist coalition spend two days combating the One Sith - until, Cade, Jeriah and Deliah confront Darth Krayt in his throne room as their Sith Temple falls. During the confrontation however, Krayt makes sure to kill Deliah prior to his own death at the hands of Cade Skywalker. This battle cost many Jedi their lives, weakening the New Jedi Order's seemingly growing power.
o The One Sith finally fall - however, the Fel Empire attempts to reinstate its authority, something Admiral Stazi doesn't approve of. There is a conflict between the two factions and the Battle of Coruscant (II) ensues. The Jedi intervene during this battle, but, this time the majority of them stand by the side of the Galactic Alliance Remnant, the Galactic Alliance Remnant claim victory, and the Fel Empire retreat back to the Sartinaynian system.

139 ABY

o The Treaty of Commons is signed on Bastion; and the Fel Empire surrenders to the returning Galactic Federation of Free Alliances, thus, all worlds previously protected by the Galactic Federation of Free Alliances are expected to follow the Galactic Alliance Common Charter once more, including the Fel Dynasty. Order returns to the Galaxy.
o Cade Skywalker goes into self-exile, as the Jedi High Council on Taivas intend to unravel their Order once more to the world, and re-model themselves on Tython, based on the Jedi Order's original Temple - and a lot closer to Coruscant. The New Jedi Order begin to once more thrive.
o The last remaining Sith Lord of the One Sith, Darth Null, awakes from his "hibernation", only to realize there is no longer a faction to return to. He begins his search for more dark jedi.