The Star Forge was a massive Starship and Fighter factory employed for use by the Sith during their war with The Old Republic.
The Star Forge is in place over the once incredibly advanced world of Lehon, a world which was populated by a native species called the Rakata and the crews of numerable vessels which had crash landed on the mysterious planet over the ages. It's location was lost for ages until Revan found it once again along with the crew of the Ebon Hawk using a series of Star Maps found in other sections of the galaxy.
While originally unknown, the Star Forge's origin lies with the people of the Rakata, who created it during a period where their race was at one with The Force and held a large number of other worlds under their rule. During this time, large amounts of ships were constructed to assist in the management of their empire, and maps, protected by guardian systems, were created to direct people to this marvel of engineering.
Unfortunately for this master race, eventually a disease ravaged their race and they began to lose their connection to the force, which they are still trying to regain. The powerful Star Forge, protected by a shield on the ground in a temple, was a place of massive power for those of the Dark Side and eventually fell forgotten, a relic of a war over 30,000 years before the Old Republic came into being.
Eventually, a young, rebellious jedi named Revan and his apprentice, Malak, found the remains of the first Star Map, which directed them on to others, and then others, eventually leading them to the Star Forge, which they took control of. Twisted already by the Dark Side as a result of the Mandalorian War, the two began their conquest as they brought a massive fleet of newly constructed ships of mysterious origins to bear down upon the jedi of old.
 Eventual Destruction
Eventually, the Republic saw the fall of the massive space station after Admiral Dodonna's fleet seemed outturned at every point, thanks to the young jedi Bastila Shan, having turned from the Light, using her abilities against the fleet. Thanks to Revan, she was brought back to the light and changed sides, using her Battle Meditation to aid in the fleet in bringing down the Star Forge and ending the Sith military superiority for the remainder of the war. However, even with this done, the Republic was very much weakened, and eventually, with the loss of their fleet and with many of the jedi missing or dead, set about repairing what was a fractured series of worlds.
 Lasting Repercussions
In the waning days of the war and afterwards, the Republic had been weakened. Crime sprung up across the galaxy as few experienced men and women were left to protect the worlds, and as time went on, the jedi began to disperse or dissappear, many of their brave knights, padawans and masters having died at the hands of the enemy, or on worlds or refuge such as Dantooine.
Indeed, the destruction of the order was almost absolute, with a few masters having receeded into hiding.
Public dislike for the jedi grew, as many of them blamed the order for not handling the Mandalorian conflict correctly and eventually leading to the many jedi who did join in the fighting turning on to the dark side and on the order themselves.
 Gaming Appearances
The Starforge was the last and ending goal of Star Wars: Knights of the Old Republic, where the Star Forge was introduced for the first time to the fandom. The player has the choice to either detroy the station as a member of the jedi order, or, if they went to the dark side, use it for their own ends. Either way, by the time the next game rolled around, the Star Forge would no longer be an issue, and the main character would be missing.
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