Progress brings hope, hope brings progess.
—A common Progenitor phrase, sometimes used as the Republic's unofficial motto
The Ancient Republic of Archaiam, often known instead as the Progenitor Republic, was the official government of the Progenitor and Progenitor Human races following the official dissolution of the Progenitor Protectorate, which itself followed the Progenitor Ecumene. It became a member of the Diet of the Ethereal Demesnes, and almost immediately possessed outsize influence due to the respect the Ethereal Human race in general held for the Progenitors. The Republic was even directly consulted on virtually all important matters in the sector the vast majority of their population lived in, the Eidolon Expanse sector in which Archaiam and the Archaiam System were located.
During the Celestial-Rakata War, the Progenitor Protectorate and the Kalendin Union-of-Nations fought alongside the Ethereal Empire as allies of the Celestials. However, in the course of the fighting, all three suffered devastating defeats, just as the Celestials did. The Kalendin never fully recovered, and effectively went extinct in the galaxy within a mere few millennia. The Progenitors, on the other hand, were driven to an even smaller population than they had already dwindled to, and thus became more and more focused on the preservation of their race. This led to the creation of the first Progenitor Humans, and, after they had reached a significant number and development, the Progenitors decided that the Protectorate, effectively a military-scientific dictatorship, would no longer suffice. Thus, it was reformed into the Republic to allow for equitable representation and governance of both Progenitor species.
For the vast majority of the region's history, the Progenitor Republic stayed out of the various wars and disputes internal to its various planetary and interplanetary governments, preferring a cordial neutrality. However, they did participate in the region's collective efforts, particularly those of regional defense, interstellar colonization, and scientific and technological development. By the time of the Clone Wars, both Progenitor races had grown their populations significantly, to such a degree that the Progenitors themselves actively participated in the campaigns to defend the Demesnes against the Confederacy of Independent Systems, using technologies such as their Programmable Matter and Projected Bolt Weapons to fight the Separatist Droid Army and Confederate Navy, and sometimes using their "cloning" method of Artificial DNA to bolster the manpower of the Demesne Defense Forces.
Following this, during the Dark Times and the Galactic Civil War, the Progenitors largely held out of the conflict, but after the restoration of the Ethereal Empire by Arius Valdayn, they finally intervened in order to bolster the defense of the Demesnes against the possibility of invasion by the Galactic Empire, though such an invasion never came. In time, they participated in the Demesnes' regionwide efforts to launch inter-galactic expeditions via Slipspace technology, alongside Ethereals, Kalendin, and Eternals and their respective, more populous, near-human descendants. Then, finally, hundreds of millennia after the four had fled their home galaxy as a result of the War of the Ancients, they all began to rediscover the Cradle.