The Jedi Order, later known as the Old Jedi Order, was an ancient monastic peacekeeping organization unified by its belief and observance of the Force, specifically the light side. The Jedi were the guardians of peace and justice in the Galactic Republic, and became the most famous of the various groups that relied on the Force for their power. Led by a series of Jedi Councils, the Order grew over the millennia despite facing many trials, most often threats from the Sith, wielders of the dark side of the Force.
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The Order currently operating onboard Stacy originate from three separate eras of Jedi history: Those of the Old Jedi Order, peacekeepers for the Old Republic. Following their destruction and subsequent reformation, the New Jedi Order originate from the days of the New Republic and the Galactic Federation of Free Alliances. The third and final category are those that have been initiated while aboard Transmigration 9.
Their headquarters, the Jedi Temple, can be found (and hard to be missed) in the City.